It takes many days and a large number of people until a new interchangeable lens is finally created by going through numerous departments, which can be roughly categorized into the four major areas of Planning ⇒ Design ⇒ Inspection ⇒ Manufacture. Tamron’s interchangeable lenses invariably go through these channels until their completion as a product.

   What kinds of interchangeable lenses should the company offer to consumers in the near future?
   The creation of a lens starts with market research.
   What kinds of interchangeable lenses do consumers want right now? Creating a lens with what specifications would encourage consumers to accept and welcome it? Based on these pieces of information, and taking into account factors such as the functions, performance, price and launch timing of a lens, the personnel in charge come up with ideas and draw up multiple plans for the next lens products.

   The key responsible officials of Tamron, including their executives, then get together to commence product planning meetings. The plans for the next lens products are presented, and careful discussions are repeatedly conducted on possible specifications, performance, prices and production efficiency. Finally, a decision is made on the lens product to be launched, marking the formal start of the development process. The outline of the lens is roughly determined at this stage, including its overall specifications and selling price.

   Please first take a look at the chart below.
   It gives a very rough outline of the flow until a new interchangeable lens is produced. In this article, I will provide an overview by explaining in order the necessary processes of Tamron’s lens manufacture through this flowchart, from planning until completion as a product.

   To create a new lens product, it is necessary in the planning stage to strike an optimal balance among the five essentially conflicting conditions. This is likely the most important point in planning a new lens product, and if due attention is not given to this examination process, it is difficult to create a product that truly resonates with customers.

・ Target customers
・ Cost (production cost, selling price)
・ Depictive performance
・ Functions
・ Size, weight

   Regarding the target customers assumed for a given product, a decision is made on whether it is aimed at entry-level users, veteran users, or professional photographers. The required performance and functions and the price differ according to this decision.
   Placing the topmost priority on the depictive quality inevitably results in a higher price, and it will be necessary to accept the fact that it could then be a large, heavy lens. If aiming for a reasonably priced lens while incorporating good performance (excellent image quality) and functions (AF and vibration compensation), it would be a very difficult challenge in ways that differ from those for a high-priced lens boasting superior performance. Both the design divisions and the production divisions (the plant) will have to shoulder the burden of resolving this challenge. At the same time, if the designers and the plant personnel work hard to successfully reduce the price as much as possible for the final product, this will no doubt make the customers happy.

   It is said that achieving the right balance for these five conditions is the most difficult challenge in the process leading from the planning for a new lens until the final decision is made to release it as a new product. This is the work for the departments marked with ① on the flowchart above.

   Once the final decision is made to create the lens product, the development departments marked with ② on the flowchart commence their development work on the lens.
   The development departments in charge of lens design comprise around four R&D units at Tamron. Examining the target values for the lens decided on at the product planning meeting, the engineers in these units now engage in lens design.
   The departments in charge of optical design establish the basis for creating a lens with ideal depictive performance by selecting from what is said to be hundreds of different types of optical glass materials with as much efficiency as possible, establishing their combinations and configurations, and creating the design drawings.

   Concurrently with optical performance, the departments responsible for mechanism design carry out the design of the lens barrel (main barrel, lens frame) to anchor the configured optical glass elements and ensure smooth movements for the movable lens element groups, and also design the mechanisms for AF and VC, etc.
   The electronic design department is in charge of the overall management of the electrical communication systems used for the exchange of information for AF and VC (vibration compensation) mechanisms and with the camera body, etc.
   The department responsible for the design of the manufacturing processes, which ensures that the lens frames and parts designed can actually be produced and assembled at a plant as assumed, is the production engineering department (also in charge of designing the inspection and adjustment equipment), which is in fact a very important department for the assembly of lenses.
 

   In the old days, the flow for lens design used to move in just one direction in a strictly vertical structure, as a product moved, upon the completion of the optical design, to barrel and mechanism design, after which it then proceeded to the production shop floor (factory). Nowadays, however, such an old-fashioned design style seemingly will not cut it in order to create a superb lens matching the latest digital cameras with a high pixel density.
   In the current process, as soon as the optical design work begins, the design of the lens barrel and the mechanisms and electronic components starts concurrently, along with the development of production engineering technologies. The design process of a lens therefore moves forward as a complicated whole, with the various different areas in step with each other. Along the way toward completion, the personnel in charge of each area sometimes make concessions to others, while not budging an inch at other times, thus forming a horizontal rather than a vertical type of design approach.

   With the design process well underway and the overall direction roughly determined, prototype model production starts as deemed necessary. It is from around this phase that the QA & QC Department begins working in full swing. Shown in ③ on the flowchart, this department is a key player in ensuring excellent quality without fail.

   In fact, the work of the QA & QC Department on a new product essentially starts as soon as product design work commences. For example, even for a small part, a thorough inspection is conducted to check whether it conforms to Tamron’s quality standards. Naturally, the parts delivered from supplier plants are also subject to rigorous inspection, and for every small piece of material to be used, a thorough chemical examination is carried out to check whether it has any environmental impact.

   When a prototype lens is completed, it is inspected in all aspects by the QA & QC Department. As well as performance tests, thorough checks are conducted for durability, operability and the actual operation of each mechanism, taking test photographs as necessary. Rigorous evaluations are also conducted to assess whether the initial design values and design targets have been achieved.
   If it is considered to be acceptable, a mass production trial starts on the actual assembly line of a plant. For the completed prototype lens for mass production, both the QA & QC Department at the plant and the QA & QC Department of the Head Office independently conduct inspections again. Only when it is confirmed that there are no problems does the mass production of the product formally begin.
   This is the stage marked by ④ on the flowchart.

   For an interchangeable lens, the vitally important parts are naturally the groups of optical glass lenses. But it also goes without saying that an interchangeable lens does not consist solely of optical glass lens elements, with the lens barrel for fixing the optical lens elements and the electronic components such as AF and VC systems among other key parts.
   The lens barrel (main barrel) is a component that is just as important as the optical glass lens elements in an interchangeable lens, so I will provide explanations of it and the other components in the next blog.