March 13, 2014
Canon Detachable Lenses: The Raw Materials
Unbeknownst to the wide scope of lens types and products, the initial process of gathering research about Canon’s lenses was quite a feat. There are many different types of lenses and housing units that fall into the category of the “detachable” sort. For the sake of capping the information in our papers, my group decided to focus on the general materials needed to construct the barrel and specifically addressing one of the key lens components in the frame, the fluoride crystal lens, which is specially synthesized in-house for Canon camera lenses. The fluoride lens was revolutionary in its ability to correct chromatic aberrations, which distort color focus when capturing a photo. The need to acquire more raw fluoride prompted Canon to devise a way to synthesize fluoride using other more common materials. Combining the fluoride lenses with general optical lenses and a few other lenses creates a balance that corrects each one’s flaws to produce a better photo capturing device. The acquisition of raw materials is dense in information and heavily laid with processing techniques that, to a common individual, may seem overwhelming, as I have learned. Along with the raw materials used in the specialized Canon fluoride lens, I will be discussing the general materials used in the processing of the barrel and the materials used to assemble everything together.
There are many types of glasses and plastics used today for lenses that each have their individual qualities that suit a specific purpose. The Canon camera lens utilizes a fluoride optical crystal in junction with basic optical glass lenses to better the results in photography. The company produces many of the optical lens parts and the lenses themselves at the Malaysian and Taiwanese headquarters (Canon-Asia). Specifically, it is in the Canon Optron Inc. headquarters in Japan where they produce and sell their optical crystals and vacuum evaporation materials for the camera lenses. The company first began developing fluoride at the Toride factory of Canon Inc. in 1966 before Optron Inc. was established as a separate division in 1974 which then became a subsidiary of Canon Inc. in 1983. (Canon Inc.). Canon Optron has mass produced fluoride since 1968, to use in correlation with optical glass. Fluoride’s properties include low refraction, low dispersion, and anomalous partial dispersion which all contribute to a finer quality of lens (Canon Optron Inc). The synthetic fluoride must be prepared through melting and casting techniques. Synthetic fluoride can be produced from beryllium fluoride, hydrogen fluoride, zinc fluoride or calcium fluoride, which will be presented as an example in the next paragraph. It is also important for the calcium fluoride to be rectified of any impurities in order to produce the best quality lens.
Though my research into the process of creating the crystal lens, I stumbled upon a numerous patents, specifically for the production of synthetic fluoride using calcium fluoride, claimed by Canon Inc. Each patient varies in processing techniques and types of scavengers used in the creation of the lens. I have tried to focus on the general and most commonly seen process and chemicals used in order to shape the foundation to which lenses are produced. The process begins with the raw material, chemically synthesized calcium fluoride, in powered form. Calcium fluoride is an ionic compound of calcium and fluorine, which occurs naturally as the mineral fluoride. The fluoride raw material is prepared through the reaction of calcium carbonate and hydrogen fluoride, regulated to achieve its desired purity, which produces a synthesized powdered calcium fluoride (CaF2). The reaction is as follows: CaCO3+2HF→CaF2+H2O+CO2. The CaF2 is then dried out to remove any moisture (Ohba). Calcium carbonate is a common substance found in rocks where the geologic settings consist of an enormous carbon reservoir, such as calcite, aragonite, limestone, and chalk, all which are pure calcium carbonate minerals. The minerals are extracted by mining or quarrying these rocks to later be combined with hydrogen fluoride (The European Calcium Carbonate Association). Calcium carbonate can be found or it can be prepared from calcium oxide when water is added. The other component to the equation is hydrogen fluoride, a colorless gas. Hydrogen fluoride is produced by combining sulfuric acid and pure grades of the mineral fluorite, commonly known as fluorspar, which can be found in China, Mexico, Southern Africa and Russia (The Essential Chemical Industry Online). As well, hydrogen fluoride can be produced from the extraction of phosphoric acid from various minerals. These raw materials can be sourced from various places and which is utilized is simply based on the sources quality and Canon’s price range.
After combining the primary raw materials to create a solid powder, the secondary raw material, that is the calcium fluoride, is then refined in a crucible. They are fused together in a time and temperature controlled environment in order to achieve the desired material (Virtual Lens Plant). After fusing, a scavenger element, such as zinc fluoride or strontium, is added to remove any remaining oxygen. The material is then melted down and allowed to cool naturally, stimulating the growth of the crystal structure. Once cool, the crystal is crushed and cast into a fusing machine, melted once again, mixed/churned, clarified, then homogenized to get rid of air bubbles (Kubaczyk). The cooled crystal is then quality tested to check for defects then allowed to be shaped and formed into lenses (Virtual Lens Plant). Depending on the type of lens to be made, the crystal is then grinded using a diamond milling tool. Due to intense thermal stress, the shaped synthetic fluoride is treated in an annealing furnace which once again heats up the material and is cooled. From here the crystal is polished to a specified roughness, creating a transparent lens and eliminating any visible machine marks. Polishing rouge, such as cerium oxide and water, is used to help polish the outside layer (Kubaczyk). Cerium oxide is of a rare earth metal and the result of calcination, or roasting, of cerium oxalate or cerium hydroxide (DaNa). It is unknown which polishing rouges Canon utilizes, cerium oxide and water is merely an example of one type I found to be used often. After another inspection, the lens is finished off with an application of an anti-reflective film coating or an evaporative substance after an initial cleaning in an ultrasonic washing basin (Virtual Lens Plant). These thin films are the result from the mass produced of evaporation materials, first manufactured at Canon Option in 1977. There are many different types of films Canon utilizes for specific lenses, to specifically name two: Super Spectra Coating and Subwavelength Structure Coating (SWC). The materials used in these coating include, but are not limited to, compounds such as SiO2, MgF2, AL2O3, ZrO2 (Canon Option Inc.). The type of film used differs by lens but all minimize ghosting and flare caused by reflected light (Canon Inc.).Trying to find more information on the specific raw materials used per coating type proved to be futile, I suppose for copyright purposes Canon would not publically release them.
After the synthetic fluoride lens is complete the next step would be to assemble the whole lens piece that attaches to the camera. The assembly of the lens system is done entirely by hand to avoid damage to the crystal lenses (Kubaczyk). There is no specification on the precise materials used by Canon to produce their barrel and sub-barrel pieces but the most common materials used are aluminum, stainless steel, beryllium, and titanium (Bayar). As an example, aluminum is super lightweight, inexpensive, and easily machined but is softer than most metals. Aluminum is a secondary raw material and is not found in a pure state in the earth, only in an alloy form, commonly found as aluminum oxide from bauxite (Lecture Notes, 3/04/14). Bauxite can be extracted from depositories in tropic and sub-tropic areas around the world but must be processed into pure aluminum oxide (alumina) by being subjected to a caustic soda solution before it can be converted to aluminum by electrolysis (European Aluminum Association). Once again the sources for whole-sale aluminum are many and it proved to be near impossible to identify where the Canon Company sourced their metals from. There is also the practice of utilizing polycarbonate material and the common ABS plastic to construct the barrel where the lens is placed in. Polycarbonate plastics are long-chain linear polyesters of carbonic acid and dihydric phenols, most commonly bisphenol A (PTS, LLC). ABS plastic is in the category of thermoplastics and is a co-polymer of acrylonitrile, butadiene, and styrene, in which each raw material contributes to the plastic’s structure (PTS, LLC). ABS plastic is the result of crude oil being distilled in an oil refinery and going through the process of polymerisation or polycondensation to form a solid material. This solid material is then melted, shaped, and solidified to achieve the ABS plastic (PlasticsEurope). One example distributor of these plastics is the Polymer Technology & Services, LLC but it is unknown whether Canon is a customer of their business. However, there is a manufacturing subsidiary to Canon Inc., Canon Mold Co, Ltd, which specializes in the manufacturing of plastic and metal molds for the company. Although I got far enough to find the manufacturer of the barrel pieces, I was unable to find the source of the raw materials that are being used by the company. Like most other large corporate companies, Canon would find suppliers of raw materials that are able to give them the best price for the best product. They may not have a specific supplier of one material over an extended period of time if another offers a better partnership.
The material used to construct the barrel is determined by the type of lens used and what its function will be. Adhesive cements, such as that of Canada balsam, are used to bond the lens to the barrel. Once again, the type of adhesive used by the Canon Company is disclosed but Canada balsam tends to be frequently used and recommended by do-it-yourselfers online. Canada balsam is made from the resin of balsam fir trees found in the North American boreal forests (Natural Standard). The turpentine produced has a high optical quality and a similar refractive index to crown glass, making it optimal for optical lenses to cement the lens and barrel or other attachments together. O-rings are also utilized in the assembly of lenses in substitute or in junction with the use of cements. They are most commonly made from rubber materials including but not limited to: PTFE, Neoprene, silicone and Fluorocarbon (Viton) (ACE Seal). Natural rubber, for example, is derived from rubber trees, which are tapped to harvest the milky-white sap, called latex, to be dried and made more durable through vulcanization. The trees are mainly Latin American-derived that were transplanted to Southeast Asia, India, Sri Lanka and Africa (Freudenrich). However, most rubber today is synthetically processed, in a similar way to plastic, through the process of polymerization (Rees). Through some searching, the online company O-Rings West claims to have Canon as a customer of their product (oringswest). There are other components to the Canon lens that have little information available in terms of the specific materials used by Canon for their products, which is why we chose to briefly mention them but not go into full detail. These components include the iris diaphragm which regulates the amount of light passing through the opening as well as the shutter which limits the time in which light is passing through. Both of these components may be made from plastic or metal, depending on the price and type of camera lens. There is also the paint used on the outside of the barrel which we also chose not to address but is still
In terms of raw materials, most of them are introduced during the manufacturing of the camera lens. Canon does have a recycling program where customers can mail in their old products however there is no information on the process of disassembling the returns nor any information is published that may include material introduction (Canon Direct Store). One of the major challenges when researching the production and materials used in camera lenses was the wide variety of products available. Determining where certain raw materials come from is difficult when you want to go from general to specific. As stated in Canon’s 2004 annual report with the United States Securities and Exchange Commission, they dictate who they will buy raw materials from based on the supplier’s environmental friendliness, quality of materials, cost of materials, stability of supply and financial condition. At any point in time Canon may contract with any number of suppliers which makes it difficult to source their material through basic online research. This is why I chose to keep a more basic outlook when it came to sourcing of primary raw materials and looked at the general common materials used. Restricting what I focused on and how far I probed into the production of raw materials limited what I could write in such a short amount of space but allowed for a more general view of the production of lenses.
There are many sources from which raw materials are acquired in order to produce a Canon camera lens. Many of these sources are natural, rock and oil based, and many are synthetically produced to emulate natural materials. As natural materials are being used up we must compensate by developing synthetic forms of these materials in order to maintain our product manufacturing. Through my findings I have discovered big companies do not fully share their sourcing information and the further I delve into the research the harder it became to uncover information. Researching one type of Canon lens was technically examining the process of lens making as a whole. The full spectrum that makes up the different types of lenses and their parts was not addressed in my report, which is quite amazing when you think about it. In today’s society no one really pays attention to the small details like what goes into making certain products and even if they wanted to find out it has proven to be difficult to unearth. After doing this project I have a new view on how materials are utilized to make certain objects. It is quite unnerving to realize that we cannot truly know how some things, so prevalent to everyday life, come about. From raw materials to a full on product, many companies choose to remain silent.
"A Guide to ABS." Polymer TEchnoogy and Services LLC. N.p., n.d. Web. 09 Mar. 2014. <http://www.ptsllc.com/intro/abs_intro.aspx>.
"A Guide to Polycarbonate in General." Polymer Technology and Services LLC. N.p., n.d. Web. 07 Mar. 2014. <http://www.ptsllc.com/intro/polycarb_intro.aspx>.
"About Us." Canon in Asia. N.p., n.d. Web. 07 Mar. 2014. <http://www.canon-asia.com/personal/web/company/about>.
"About Us ｜Company Info and History." Canon Optron Inc. N.p., n.d. Web. 07 Mar. 2014. <http://www.canon-optron.co.jp/english/profile/overview.html>.
Canon Inc. Canon Announces New Anti-reflective Lens Coating Technology. Canon Global. N.p., 17 Sept. 2008. Web. 10 Mar. 2014. <http://www.canon.com/news/2008/sep17e.html>.
"Cerium Dioxide - Material Information." DaNa. N.p., n.d. Web. 10 Mar. 2014. <http://nanopartikel.info/en/nanoinfo/materials/cerium-dioxide>.
Chiba, Takao. Method of Heat Treating Fluoride Crystal. Canon Kabushiki Kaisha, assignee. Patent US 6702891 B2. 08 Mar. 2000. Web. < http://www.google.com.tr/patents/US6702891>
"Common O-Ring Materials." ACE Seal. N.p., n.d. Web. 08 Mar. 2014. <http://www.aceseal.com/o-ring-materials.html>.
"Evaporation Materials｜Products and Technologies." Canon Optron Inc. N.p., n.d. Web. 05 Mar. 2014. <http://www.canon-optron.co.jp/english/evaporation/index.html>.
Freudenrich, Ph.D. Craig. "How Rubber Works." HowStuffWorks. HowStuffWorks.com, 14 Oct. 2008. Web. 10 Mar. 2014. <http://science.howstuffworks.com/rubber1.htm>.
"How Plastic Is Made." PlasticsEurope. N.p., n.d. Web. 12 Mar. 2014. <http://www.plasticseurope.org/what-is-plastic/how-plastic-is-made.aspx>
"Hydrogen Fluoride." The Essential Chemical Industry Online. N.p., 18 Mar. 2013. Web. 10 Mar. 2014. <http://www.essentialchemicalindustry.org/chemicals/hydrogen-fluoride.html>.
Kubaczyk, Daniel M. Photographic Lens Manufacturing and Production Technologies. Diss. Massachusetts Institute of Technology, 2011. N.p.: n.p., n.d. PDF.
"Canada Balsam." Natural Standard - Database Home. N.p., n.d. Web. 10 Mar. 2014. <http://www.naturalstandard.com/index-abstract.asp?create-abstract=canadabalsam.asp&title=Canada%20balsam>.
Ohba, Tomoru, and Toshio Ichizaki. Fluoride Crystal, Optical Article, and Production Method. Canon Kabushiki Kaisha, assignee. Patent US 6270570 B2. 27 Mar. 1998. Web. <http://www.google.com.tr/patents/US6270570>
"Optical Crystals." Canon Optron Inc. N.p., n.d. Web. 06 Mar. 2014. <http://www.canon-optron.co.jp/english/fluorite/>.
"O-Rings West." O-Rings West. N.p., n.d. Web. 08 Mar. 2014. <http://www.oringswest.com/>.
"Production Process of Aluminum." European Aluminum Association. N.p., n.d. Web. 07 Mar. 2014. <http://www.alueurope.eu/about-aluminium/production-process/>.
"Recycling Program." Canon Direct Store. N.p., n.d. Web. 11 Mar. 2014. <http://shop.usa.canon.com/shop/en/catalog/product-accessories/recycling-program>.
Rees, Dia. "Recycling Rubber." Practical Action. Practical Action: Technology Challenging Poverty, 01 Jan. 1998. Web. 10 Mar. 2014. <http://practicalaction.org/waste-management-answers>.
Schwertz, Katie M., and James H. Burge. Field Guide to Optomechanical Design and Analysis. Bellingham, WA: SPIE, 2012. SPIE Digital Library. Web. 7 Mar. 2014.
Virtual Lens Plant. Canon Camera Museum | Technology Hall | Virtual Lens Plant. N.p., n.d. Web. 05 Mar. 2014. <http://www.canon.com/camera-museum/tech/l_plant/main.html>.
"What Is Calcium Carbonate?" The European Calcium Carbonate Association. N.p., n.d. Web. 10 Mar. 2014. <http://www.cca-europe.eu/what-is-calcium-carb.html>.
13 March 2014
The Embodied Energy of a Canon Detachable Lens
When observing energy usage in product development, people tend to solely focus on the manufacturing process and often neglect the energy required in areas such as raw material extraction and product disposal. This is a narrow perspective. To be energy conscious in this resource-limited world, we should consider the embodied energy use, or the overall energy use required throughout the course of a product’s entire life cycle. I would like to explore this concept of cumulative energy use more deeply by going through the life cycle of a Canon camera detachable lens and its complimentary components.
A general DSLR camera lens is made of the following parts: The plastic or metal barrel, a rubber ring, cement adhesives, and finally the lens themselves. While I will discuss the energy requirements of all of these parts, I will put emphasis one kind, the fluorite lens. While there is a vast selection of different types of lenses, my group decided to concentrate our research on this particular type because it is perhaps one of the most essential lens situated within the barrel, as it’s main purpose is to correct chromatic aberration (i.e. defining focal points).
Camera lenses do not pop into existence in the factory out of thin air; the opening step is to acquire the raw materials. First, there are the primary materials that altogether make up the secondary material of ‘glass’ sheets made from calcium fluoride crystal. These are elements such as boron and compounds such as hydrogen fluoride, zinc fluoride, beryllium fluoride, and of course calcium fluoride itself (Kubaczyk). The energy input in this stage begins in the mines where human labor (mechanical energy) and machines that run on fuel (chemical energy) mine for the mineral in deposits all over the world, with the most notable being in South Africa (E.I.A.). However, because natural fluorite is too small to be used for photographic lenses, Canon began to make larger artificially crystallized synthetic fluorite (fluoride) crystals in their laboratories. The artificial fluoride crystal production method for Canon lenses is outlined in patents claimed by Canon Inc. To refine a fluoride crystal, the raw material (Calcium fluorite and scavenger elements like zinc fluoride or strontium) is placed within a crucible in a furnace filled with reactive gas and then vacuum atmosphere (Canon). The raw material must then be heated at a temperature just below the melting point for four to thirty hours and be melted within a vacuum or inert gas atmosphere to remove oxygen, which dehydrates the material at 100 to 300 degrees Celcius (Oba). The fluoride crystal then must be heat-treated or annealed, a process of sequential heating and cooling to relax the stress inside the crystal (Chiba) . This process takes a lot of energy and time, which is one of the reasons why production cost is so expensive. The fluorite is now in its final crystallized form.
These furnaces use thermal energy, which is a type of internal kinetic energy whose properties are increased proportionately at higher temperatures through conduction, convection, and radiation (Hughes). This energy, increased by the high temperatures in furnaces, prompts the chemical change from raw mineral to crystal. The most popular technique for treating fluorite is the Bridgman-Stockbarger method using machines such as the KRF-1 Apparatus, which is sustained with stabilized power supply and electrical voltage that is input into the lower and upper heaters (Krivandina). In this raw material stage, crude oil is a huge energy resource. In 2013, around 1,206,708 kl were used in the manufacture of the raw materials/parts of Canon products alone (Canon).
After the synthetic crystal is formed, all materials are measured and placed into a mixer and blended that is most likely powered by electrical energy. The product is then prefused in another crucible under strict time and temperature control, using thermal energy in a furnace to become molten glass. After the glass is poured in a palate and is allowed to cool, it is simply crushed by human hand using the mechanical energy from labor. Next is the fusing and cooling stage, the most important part. The crushed glass is cast into a fusing machine and melted at 1300 degrees Celsius (Canon), mixed and churned, clarified (to get rid of solid matter), and homogenized in to a liquid to be free of air bubbles. Poured into a shaping machine, liquid glass is shaped into its final sheet form that is gradually cooled to room temperature while traveling on a conveyer belt through a temperature gradient type slow cooling furnace.
The final sheet of glass/crystal is used as the material for individual lenses. All of these steps utilize many heating methods. Though the furnaces used in glass making can be powered by oil, gas, or oxi-fuel, electrical heating is the most efficient technique since 95% of energy is converted into heat (Plum). To sum up the amount of electricity used in the year 2013 for canon products, 1,732,185 MWh of electricity was estimated for the amount used during development (Canon).
As for the other materials making up the barrel, there is cement for adhesives, hard plastic for structure and side components, and metal for parts such as the iris diaphragm or shutter. Though the specific adhesive for Canon products is undisclosed to the public, a possible cement used for the lens is a turpentine called Canada Balsam. The energy requirement of this raw material extraction is very low compared to the fluorite crystal. Its resin is gathered from the balsam fir, which mainly grows in North America. The main energy requirement of Canada Balsam actually goes towards shipping and transportation to Japan, which will be discussed in a later section. As for plastics, the plastic used in Canon lens is likely to be an ABS plastic (acrylonitrile butadiene styrene) for its electrically insulating and long lasting qualities. Such companies as PlasticsEurope, industrial production of 1 kg of ABS plastic uses on average 95.34 MJ (26.48 kWh) and is derived from natural gas and petroleum. The company claims that ABS plastic is more sustainable and energy efficient than other material options. As quoted a distributor’s website, “If plastics had to disappear and to be replaced by alternatives, the life-cycle energy consumption for these alternatives would be increased by around 57% and the GHG emissions would rise by 61%.” (The Plastics Portal). Though this may be a biased corporate opinion, it is a viewpoint worth considering. Metal is a small but essential part. There are a variety of metals used such as aluminum and stainless steel. Aluminum takes an enormous amount of electrical energy as well as some other fuels like natural gas and liquefied petroleum gases. According to the U.S. Energy Information Administration, aluminum production takes around 300 trillion BTA (British thermal units = 1055 joules per unit) per year. Steel takes even more energy as reports show that the steel industry uses 1.1 quadrillion BTU as fuel energy per year (E.I.A.). Canon Inc. is supporting this energy usage by using the metal industry as a supplier for the material for their lenses. Finally, rubber makes up the O-ring in the lens. Synthetic rubber involves mastication, shaping, moulding, and other processes that are powered by thermal energy using electricity. Eventually, the rubber is heated at 150 degrees Celcius in a process called vulcanisation (Practical Action). This goes to show that even the smallest part can contribute to a product’s ecological footprint.
Manufacturing, Processing, and Formulation
The energy sources that are used in the manufacturing, processing, and formulation of the camera lens are not much different than those used in the material processing stages of production. First, the secondary material, or the fluorite crystal ‘glass’ discussed in the previous section must be pressed and formed into shape. The first grinding step is a rough grinding to begin lens curvature; it is usually done with iron abrasives and diamond milling tools in specialized grinding machines (Kubaczyk). Grain abrasives are added and as the sizes get smaller, more grinding force is needed. Next, after glass weight is calculated and determined, it is cut with a diamond cutter. Larger aperture lenses are cut by hand using heat (mechanical plus thermal energy). More thermal energy input is required as glass is further heated and pressed into shape. Automated pressing machines are used for small lenses are larger lenses are pressed by hand. A second annealing takes place to remove internal thermal stress. To do this, the lens is heated to 500 degrees Celcius in an electric furnace (Canon). The energy required in all of these processes is powered by machinery, which in turn is powered by electricity. The machines used for pressing and cutting all use electrical energy, which contribute to the 1,732,185 MWh of electricity usage that was mentioned previously. Canon also used 43,160 km3 of gas, 7,663 kl of /heavy oil for manufacturing its products in 2013 (Canon). All of these resources power the final rough grinding, fine grinding, polishing, alignment, and coating processes to produce the final fluorite lens itself.
The assembly process is interesting because there is minimal machine use involved. The energy use in this step is quite low as lens specialists instead of machines are the ones who work with assembly and cleaning. The energy requirement here can be summed up as human mechanical energy. Perhaps the most prominent electrical input in this area is the energy required to perform the ultrasonic washing of the lens and the vacuum machine for lens coating.
Distribution and transportation
Transportation is a huge energy consumer. Canon is a big participant in the globalized economy. According to consolidated historical data, Canon made over three million sales overseas in the year 2013. Shipping and transport must be considered to distribute Canon products to the retail outlets or middle distributors. Since Canon distributes its products all over the world, cargo ships that transport the lens from their various factories use shipping fuel to get their products and parts from one place to another. Canon tries to build the part-manufacturing factories closer to their assembly factories to cut costs (Peters). The largest Canon factory is the Oita Factory, in Oita, Japan. In 2004, this factory built another sector for distribution right next to its parts-production factory (JCN Network). Though their main focus was cost reduction, they also cut down on shipping fuel. Even so, shipping costs, equating to shipping fuel, has increased since 2006 because of increased sales overseas (Canon). The crude oil amount used for shipping by Canon for the year 2013 is estimated to be a large total of 136,659 kiloliters (Canon). This makes sense as a normal speed containership may take up to 225 tons of bunker fuel per day to move at 24 knots (Geotrans), that is 2.3 MJ/ton-mile (Cannondesign). Although these fuel amounts are not so easily lowered, fuel use can be decreased if containerships travel at lower speeds. There are other slower speed options such as those that come with slow steaming, extra slow steaming, or minimal cost (Geotrans). However, since the normal speed is the most commercially acceptable, it is most likely that Canon, a large corporate company, would be using the quickest way to transport their goods.
Transportation energy usage must also encompass raw material transport. As pointed out previously, Canada balsam, which often grows in Canada, is the adhesive used for lens assembly. Its resin must eventually get to one of the lens factory. For example, if the factory of interest were the Oita factory in Japan, the resin would have to be shipped all the way from across the globe to be used as a material. The same kind of fuel expense is the same for steel and rubber.
During the lens usage, there is usually no energy involved in maintenance. It is simply attached onto the camera and detached from the camera.
Recycling and Waste Management
Though fairly rare, there are recycling centers for lenses available. If not participating in Canon’s own recycling program, a Canon lens owner can choose to recycle the lens to such places as Gazelle.com, or CameraRecycle in Australia. “Over 90% of the plastics and metals in cameras, batteries and accessories can be recovered and used as raw materials to make new products such as stainless steel, plastic park benches, plastic fence posts, garden edging, tree spikes and much, much more” (Camera Recycle). To melt plastics and metals, a lot more thermal energy powered by electricity would need to be used. According to the Energy & Environmental Science Journal, the incineration of polymers is the most traditional model of ‘recycling’ to get energy from plastic, similar to the energy of petroleum fuel (Baytekin, Grzybowski). Many of these incinerating facilities are in Germany, which adds to the energy cost of transportation mentioned in a previous section. There are also new thermal technologies for treatment of plastic, which converts polymers into smaller fragments to retrieve valuable chemicals (Baytekin, Grzybowski).
I could not find any information on recycling fluorite lens. I suspect that because of the excessive processing and chemical enhancements that it goes through during production, it is no longer safe to be reused as raw material.
Rubber can be recycled for material reuse, through at a huge energy cost. First the rubber goes through physical changes as it is torn apart and cut into pieces. Then it is chemically treated in a process called reclamation and thermally treated with pyrolysis, combustion, and incineration.
Though recycling is considered a ‘green’ practice that the environmentally conscious should pay attention to, the world must also consider the energy and resource costs that go into the processing of material. Do the gains outweigh the costs? According to the book Cradle to Cradle, materials that are recycled are actually downcycled, meaning that recycled materials no longer retain the value that they originally began with (Mcdonough, Braungart). Companies should consider upcycling or reuse methods that upgrade the value of the material from the product instead of downgrading it.
Thoughts on Research
Through my research on the embodied energy of the Canon Detachable Lens as well as illumination on raw materials and wastes from my fellow group members, I have realized that Lens production is an energy intensive process. Though Canon attempts to be more environmentally conscious, it does not cancel out the fact that the energy and resources consumes involves everything from mining to distribution. As the years go by and consumer demand goes up, Canon’s ecological footprint will only get bigger. Overall, the project was personally insightful for me. The knowledge that I have gained from the research has enlightened me to view production more critically and has made me see the products that I use in a new light.
"Abies Balsamea." Wikipedia. Wikimedia Foundation, 03 Sept. 2014. Web. <http://en.wikipedia.org/wiki/Abies_balsamea>.
Agureev, S. A., L. Levitin, and V. D. Tokarev. "Science for Glass Production." Glass and Ceramics 70 (2013): 9-10. Web.
Baytekin, Tarik H., and Bartosz A. Grzybowski. "Retrieving and Converting Energy from Polymers: Deployable Technologies and Emerging Concepts." Energy & Environmental Science 6.12 (2013): 3467-482. Web of Science. Web.
Brooks, David. Lenses and Lens Accessories: A Photographer's Guide. Somerville, MA: Curtin & London, 1982. Print.
CameraRecycle Australia. "Why Recycle." N.p., n.d. Web. 13 Mar. 2014. <http://www.camerarecycle.com.au/why_recycle.html>.
CannonDesign. "Material Life: Embodied Energy of Building Materials." CannonDesign. N.p., n.d. Web.
Canon. "Canon Historical Data." Canon, Inc., n.d. Web.
Canon. "Canon Sustainability Report." N.p., n.d. Web.
Canon. "Infobank." Canon Professional Network. Canon, n.d. Web. 13 Feb. 2014. <http://cpn.canon-europe.com/content/education/infobank/lenses/fluorite_aspherical_and_ud_lenses.do>.
Canon. "Virtual Lens Plant." Technology Hall-Virtual Lens Plant. Canon, Inc., n.d. Web. <http://www.canon.com/camera-museum/tech/l_plant/>.
Capper, Peter. Bulk Crystal Growth of Electronic, Optical & Optoelectronic Materials. Chichester: J. Wiley & Sons, 2005. Print.
Chiba, Takao. Method of Heat Treating Fluoride Crystal. Canon Kabushiki Kaisha, assignee. Patent US6702891B2. 9 Mar. 2004. Print.
E.I.A. "U.S. Energy Information Administration." Manufacturing Energy Consumption Survey (MECS) Steel Analysis Brief. U.S. Department of Energy, n.d. Web. <http://www.eia.gov/consumption/manufacturing/briefs/steel/index.cfm>.
E.I.A. "U.S. Energy Information Administration." Manufacturing Energy Consumption Survey (MECS) Steel Analysis Brief. U.S. Department of Energy, n.d. Web. <http://www.eia.gov/consumption/manufacturing/briefs/steel/index.cfm>.
"Fluorite." Wikipedia. Wikimedia Foundation, 26 Feb. 2014. Web. <http://en.wikipedia.org/wiki/Fluorite>.
Hughes, Leah. "Thermal Energy." Chemwiki. UC Davis, n.d. Web. 13 Mar. 2014. <http://chemwiki.ucdavis.edu/Physical_Chemistry/Thermodynamics/State_Functions/THERMAL_ENERGY>.
JCN Network. "Canon Announces Second Stage of Construction at New Oita Canon Plant." JCN Newswire. N.p., 4 Aug. 2004. Web. 13 Mar. 2014. <http://www.japancorp.net/Article.Asp?Art_ID=8020>.
Kingslake, Rudolf. Optics in Photography. Bellingham, WA: SPIE Optical Engineering, 1992. Print.
Kubaczyk, Daniel M. "Photographic Lens Manufacturing and Production Technologies." Diss. Massachusetts Institute of Technology. Dept. of Mechanical Engineerin, 2011., 6 May 2011. Web. 13 Feb. 2014. <http://hdl.handle.net/1721.1/69779>.
McDonough, William, and Michael Braungart. Cradle to Cradle: Remaking the Way We Make Things. New York: North Point, 2002. Print.
Miller, Michael. "Fluorspar." USGS Mineral Resources. US Geological Survey, n.d. Web. <http://minerals.usgs.gov/minerals/pubs/commodity/fluorspar/mcs-2011-fluor.pdf>.
Oba, Tomoru. Raw Material for Manufacturing Fluoride Crystal, Refining Method of the Same, Fluoride Crystal, Manufacturing Method of the Same, and Optical Part. Canon Kabushiki Kaisha, assignee. Patent US6238479 B1. 29 May 2001. Print.
Ohba, Tomoru, and Toshio Ichizaki. Fluoride Crystal, Optical Article, and Production Method. Tomoru Ohba, Toshio Ichizaki, assignee. Patent US20010001383 A1. 24 May 2011. Print.
Peters, Mark. "Canon Builds Digital Camera Parts Factory in Japan." Let's Go Digital. N.p., n.d. Web. 13 Mar. 2014. <http://www.letsgodigital.org/en/news/articles/story_2997.html>.
"Photographic Lens Manufacturing and Production." Massachusetts Institute of Technology, n.d. Web. 13 Feb. 2014. <(http://dspace.mit.edu/bitstream/handle/1721.1/69779/776202013.pdf?...1>.
The Plastics Portal. "Life Cycle Thinking." PlasticsEurope. The Plastics Portal, n.d. Web. 13 Mar. 2014. <http://www.plasticseurope.org/plasticssustainability/life-cycle-thinking-1746.aspx>.
Plum, Sven, Patrick Graf, Mark Beckers, Jonathan Boersma, Eric Van Den Dungen, Maurice Frijns, and Frank Verbakel. Advanced Heating Techniques for Glass Melting. Tech. N.p.: University of Eindhoven, n.d. Print.
Practical Action. "Recycling Rubber." Columbia Engineering. N.p., n.d. Web. <http://www.seas.columbia.edu/earth/RRC/documents/recycling_rubber.pdf>.
Rachana Group. "Rachana." Fluorite Exploration, Fluorite Mining. Rachana Global Excavation Ltd., n.d. Web. <http://www.rachanaglobal.com/fluorite_exploration_mining.html>.
Rodrigue, Jean-Paul. "Fuel Consumption by Containership Size and Speed." The Geography of Transport Systems. Hofstra University, n.d. Web. 11 Mar. 2014. <http://people.hofstra.edu/geotrans/eng/ch8en/conc8en/fuel_consumption_containerships.html>.
13 March 2014
Waste Byproducts of Camera Lens Manufacturing & Use
Although camera lenses may seem initially to be little more than fancy magnifying glasses, their production process must be highly intricate and specific to allow the lenses to perform well and deliver sharp images. Because of the fact that photographic lenses hold their value well for resale and can sometimes even appreciate in value over time, the vast majority of wastes produced by camera lenses is not in their disposal, but in the production process itself. Over time, camera lenses have evolved to include a variety of different mechanisms and features that help improve image quality, from improved glass materials to chemical anti-glare coatings. While not all of the steps of camera lens production are spelled out and publicly available, this essay will cover the general steps that are included in camera lens production and how each step produces waste via direct materials or through the wastes from the energy needed to power certain projects, as well as the waste generated across the product lifespan.
The first step in lens production is to develop the optical glass from which to cut lens elements from. Depending on what each element is being used for, the type of glass used for each element may be anywhere from extremely low dispersion to high dispersion. Low dispersion glass is used to reduce chromatic aberrations, especially in long range telephoto lenses where chromatic aberration distorts images the most (Marshall). The materials used in low dispersion, or general category of crown glass, can vary depending on the specific blend used by different manufacturers. For example, the BK7, or borosilicate variety of crown glass, includes boron trioxide, and must be worked at much higher temperatures than standard glass. This produces a number of more hazardous wastes as well as demands more energy to heat than conventional glass, indirectly increasing CO2 emissions through the energy demanded to produce it (Ray).
In order to provide a closer look at the production process and wastes that are generated, my group elected to also look specifically at the development of fluorite lenses that are used by Canon for their photographic lenses. As outlined by the fluorite crystal growing patent, fluorite seed crystals are grown by heating them to a temperature of 1500 degrees Celsius in a vacuum furnace that produces a suitable temperature-gradient for growing crystals (Stockbarger). The special furnaces are powered by heated by electrically powered graphite rods with water cooling systems. Although specifics on energy usage were not made available for waste production analysis, the furnaces were specified to use an extremely large amount of power for a relatively small amount of crystal produced (no more than 6 inches in diameter). The overall waste generated from the CaF2 crystals produced for lens production depends on where the specific energy is sourced from. The electrical energy most likely is sourced from traditional sources such as gas and coal to minimize costs, but may also be supplemented by alternative or renewable energy that Canon is sourcing in addition as outlined in Canon’s sustainability report (Canon Sustainability Report 2013).
Following the production of either glass or fluorite crystals for the raw material of the optical lens, the block or crystal itself must be ground down to the shape of a lens. The ground down lenses produce waste in the form of leftover glass material and fluorite dust. Ground down glass can be easily recycled for reproduction, and fluorite crystals when ground down are desirable because the dust can be mixed with sulfuric acid to produce Hydrogen Fluoride, which is useful in a variety of other applications (Ohba et al). Once produced, the Hydrogen Fluoride can be used for production of aluminum, enamels, other glass, etc. Therefore, the grinding process for lenses relies on either human or mechanical energy which produces waste much like the furnaces, the transfer of energy, but little to no byproducts of the process itself. Because the resulting materials are either part of the final product or can be passed onto other processes, the only wastes from this step of the process are the ones produced by the conversion of energy to power the process. Machines drawing electrical energy from power plants grind the glass or fluorite down from their unrefined shapes into the final computer-designated specifications before a final polishing of each element makes sure it is smooth and clear (Ray).
Once the lens has been ground down, it has achieved its basic shape, and then needs to be polished. An assortment of different chemicals are used by different manufacturers to polish the lenses to a sheen, but one example that I will cover is cerium oxide. The cerium oxide is used to wash over the lens as a machine polishes the glass with it, rubbing away any imperfections (Technology Hall | Virtual Lens Plant). During the process of polishing the lens, not only does the chemical come in contact with other equipment, it also becomes airborne by the pressure from the polishing process. While being polished, molecules of cerium oxide are distributed into the air, and those corrosive molecules can be dangerous even at small levels. Not only do the factory workers get exposed to airborne cerium oxide, but the chemical can still be dangerous even after being disposed of.
Cerium Oxide is a harmful corrosive if it makes contact with humans in any way: through ingestion, inhalation, or bodily contact (Cerium Oxide MATERIAL SAFETY DATA SHEET). Thus the airborne particles of cerium oxide can be harmful, but also the leftover polishing agent can be harmful if not properly disposed of. Although the waste is not extremely harmful because it is only present in small quantities, it can still have an adverse effect on the health of people, and requires careful transportation to waste management. This transportation uses gasoline and emits CO2 into the atmosphere by way of material transit.
Once the lens has been completed and polished, it can be coated with an anti-reflective coating to help improve image quality further. Canon specifically uses a nanocoating of Aluminum Oxide for its high quality coatings, and other manufacturers have individual processes as well. In the case of Aluminum Oxide, Canon uses a technology called Subwavelength Structure Coating to coat its lenses, which produces little material waste, but again requires high amounts of electrical energy to power the machinery. Aluminum Oxide itself is also considered of little danger to health because it is a metal that can be processed mostly, unless inhaled in large amounts (Srinivas). For the coating process, the primary concern of energy is excess chemicals which other manufacturers such as Pentax may use instead of the high tech Aluminum Oxide being left over, and the energy used. Although manufacturers do not disclose the chemical make-ups of their specific coatings, they can vary from silica to heavier metals depending on the refractory nature that they provide (Cicala).
The lens barrels are made differently depending on the quality of lens being analyzed, but primarily are constructed of aluminum and/or abs plastic. Some manufacturers use steel or other alloys, but those are used far less often than aluminum or abs plastic because of how easy to work with and affordable they are (Schwertz). To produce molten aluminum or abs plastic (Acrylonitrile Butadiene Styrene), heat is required to melt the materials into a malleable form to cast into a lens barrel shape. Heating furnaces common to any metallurgy facility are used for aluminum, but abs plastic requires less heat. However, abs plastic is developed from styrene, which is very toxic in gas before it is formed into the abs plastic mixture (Styrene). Thus the production process of abs plastic can leave styrene in the environment, causing toxic waste which results in toxic effects such as environmental degradation and human health risks.
The last major aspect of photo lens production is the rubber used for the outside grip of the lens barrel. Lenses include synthetic rubbers as a comfort aide for the lenses’ focusing and zoom rings, and rubber production can produce large amounts of wastes for the environment. Besides the wastes produced from the CO2 emissions of the plants manufacturing rubber and processing it, rubber production also releases Butadiene and styrene back into the environment as byproducts. Butadiene concentrations from a single reactor can reach up to 2,500 ppm in surrounding environments, which puts people and the environment as a whole at risk for contamination to the toxic materials (Placak et al). Though rubber is only used in marginal quantities in lenses, each lens requires a significant amount of rubber relative to the total materials used in its production. Therefore rubber production contributes to one of the largest sources of waste in the production process of photographic lenses.
During the lifecycle of lenses, they produce little to no waste if properly used. The vast majority of waste during the lifetime of a lens is the CO2 emissions from vehicles transporting camera lenses, as they are distributed across the world. Camera lenses do not require extra power to function, and ought not to release any more material into the environment unless they are broken physically. Camera lenses are either manual focus or powered by camera bodies, but the amount of energy required to operate autofocus mechanisms in camera lenses is negligible when compared to the power consumption of the camera body itself. Driving a small motor to turn the lens uses far less than the shutter operation to take the actual photo and the activation of the sensor of a digital camera, so camera lenses can be considered non-reliant on power. Moreover, manual lenses do not even accept electricity even if offered by the camera body.
Camera lenses can have extremely long lifetimes due to the care put into their construction as well as the simplicity of their overall construction (simplicity that does not forgo precision). Camera lenses are often resold and reused, and can have lifetimes far longer than expected. I personally have used a vintage manual film lens from the 1970’s on a modern digital SLR camera with ease, and contributed to the lifecycle of the lens when reselling it later. As camera lenses that are considered optically superior will remain sharp as time passes, their value does not decrease. In fact, it can sometimes increase over time if the lens becomes less available when manufacturing slows or stops for that particular lens.
Moreover, manufacturers such as Canon encourage recycling of camera equipment even after the lifecycle of a lens or camera body has been exceeded. When an outdated or broken lens is no longer of use to a customer, Canon accepts these lenses back and can provide reimbursement for the lenses (Recycling Program). This program encourages people to avoid throwing out camera lenses that have parts that can be salvaged and recycled for future use. The buyback program demonstrated by Canon is also used by other manufacturers, and though it is only used by a small amount of customers with these lenses, it still helps alleviate the problems of electronic waste and landfills. Any lenses that are returned to the recycling program are still lenses that could have ended up in a landfill otherwise.
If a camera lens does end up in the environment as waste, the materials are usually fairly slow to degrade. Because camera lenses are composed of durable materials such as glass, aluminum, abs plastic, and rubber, the materials can remain in the earth for over hundreds of years (Placak et al). Thus the long lifespan and recycling programs for lenses becomes more important because the lenses that do end up in the environment can leave chemicals in the earth as well as cause physical harm to wildlife and ecosystems in which they are left and do not belong. Like other man-made equipment, improper disposal is the most prevalent source of problems for waste from camera lenses. When properly disposed, recycled, or resold, camera lenses leave little environmental impact from their materials because there are easy disposal methods for their parts.
Thus camera lenses can be both incredibly complex and extraordinarily simple at the same time. From the start of their production through the end of their lifecycles, camera lenses are very unique. While camera lenses do produce some waste products such as styrene, the majority of waste from camera lenses comes from the energy production needs that they have. The raw materials and chemical byproducts from camera lenses are far less harmful than those of other products. The majority of the waste related to camera lenses comes indirectly from the conversion of energy to power plants and equipment that develops camera lenses. Because high amounts of electricity and heat are needed to form the precision elements of camera lenses, large amounts of fuel are required to power the machinery to develop camera lenses. This electrical energy required to power the machinery generates the most waste and CO2 emissions for the environment during an otherwise low-waste lifecycle of camera lenses.
Marshall, Gerald F. Optical Scanning. New York: Marcel Dekker, 1991. Print.
Ray, Sidney F. Applied Photographic Optics: Imaging Systems for Photography, Film, and Video. London: Focal, 1988. Print.
Stockbarger, Donald C. The Production of Large Artificial Fluorite Crystals. Discuss. Faraday Soc., 1949. Print.
Canon Sustainability Report 2013. Rep. N.p.: Canon USA, 2013. Print.
Ohba, Tomoru, and Toshio Ichizaki. Fluoride Crystal, Optical Article, and Production Method. Canon Kabushiki Kaisha, assignee. Patent US 6270570 B2. 27 Mar. 1998. Web.
Srinivas, A. "Result Filters." National Center for Biotechnology Information. U.S. National Library of Medicine, 28 Aug. 2011. Web.
"Technology Hall | Virtual Lens Plant" Canon Camera Museum. Canon, n.d. Web.
"Cerium Oxide MATERIAL SAFETY DATA SHEET" Cerium Oxide MATERIAL SAFETY DATA SHEET. Newport Glass, n.d. Web
"Styrene." ATSDR. Agency for Toxic Substances and Disease Registry, 3 Mar. 2011. Web.
Cicala, Roger. "All About Lens Coatings." Canon Rumors. Canon Rumors, 17 Dec. 2011. Web.
Schwertz, Katie M., and James H. Burge. Field Guide to Optomechanical Design and Analysis. Bellingham, WA: SPIE, 2012. Print.
Placak, O. R., and C. C. Ruchhoft. "A Study of Wastes from the Synthetic Rubber Industry."JSTOR. Water Environment Federation, Nov. 1946. Web.
"Recycling Program." Canon Direct Store. Canon, n.d. Web