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Quality lenses without compromise

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John Murphy discovers the story of Tamron, a well known name in the world of lenses.

Anyone with a keen interest in photography will know the name of Tamron as a manufacturer of good lenses. While some would stick with the Nikon and Canon brands, those on stretched budgets have long believed that Tamron’s lenses were as good – but much better value.

The company is now taking this message to the machine vision industry and has established a division selling specifically to this market. It has launched its marketing campaign with the slogan ‘new eyes for industry’ and is already making inroads into a market dominated by Pentax.

Tamron is not a ‘cheap’ alternative to the higher profile names in the photographic market; it is a lower-priced competitor that leads with the quality and durability of its products. It believes that the secret of winning market share is to get machine vision companies to test its products against what they are currently using and that the quality will speak for the company.

As sensor resolution increases, the quality of the image is on trial. What use is a pattern recognition system if the image of the pattern is distorted by the optics that created it, particularly if the distortion changes with time due to the rough environment of a factory automation system?

But Tamron claims that machine vision companies were asking it to come up with products for this market, and three years ago set up an operation in Germany to service the European market through a new network of distributors. While volumes are tiny compared to the photographic industry, price is not always the issue that it is in the consumer market, where the Chinese manufacturers are barking at its heels.

Tamron was founded in 1950 by the late Takeyuki Arai to make lenses for cameras and binoculars, originally as Taisei Optical Equipment Manufacturing. The name was changed to Tamron in 1950 and comes from the name of its most famous optical designer, Uhyoue Tamura.

The end of the 1950s and beginning of the 1960s saw the emergence of the single lens reflex camera. Apart from many other advantages, this offered the chance to interchange lenses on the same camera body. In fact Tamron produced the first interchangeable system called the T Mount. Tamron started to become a popular alternative in photographic circles to the interchangeable lenses offered by the top camera makers, like Nikon and Canon, because they were of comparable quality but at much lower prices – and they fitted the lens mountings. In the 1980s the company introduced its Adaptall 2 mounting system, which meant it could make its lenses compatible with most of the major camera manufacturers.

Tamron has always been highly innovative in its designs and production techniques. It was also innovative in having such confidence in the design and construction that it offered six-year warranties with its lenses. The company has never claimed to be the cheapest lens on the market, far from it, but is regarded by many as offering excellent quality in an after-market lens that often surpasses the quality of the original manufacturer lenses.

For most of its life, Tamron has concentrated on consumer markets, but in recent years has diversified into mobile phone camera lenses and industrial vision lenses.

Toshimasa Wada (pictured above) opened an office in Europe in 2003 to spearhead a sales campaign for Tamron in the industrial camera and machine vision market. He says: ‘We started making machine vision lenses about 10 years ago. We did this because we were getting a lot of enquiries from camera manufacturers when we were at exhibitions. We were not really able to respond to these enquiries, so the board decided to create a new division to address this market.

‘The introduction of our lenses into this market was very smooth, because most people already knew the name of the company from its history in the general photographic market. People know that our lenses are regarded as being very good by the photographic market and it is very good for us that people assume our lenses are also going to be good in the industrial machine vision market. The basis of our reputation in the photographic market is that we have always invested heavily in research and development compared to our competitors, and we concentrate on quality. Our prices are not the cheapest.’

The move into machine vision lenses required a significant rethink of its business model. Tamron had traditionally concentrated its marketing on consumers and worked with consumer channel partners. Clearly sales volumes are also a lot lower, but the prices are higher. Its marketing has concentrated on educating the machine vision market on the importance of the lens quality.

Wada says: ‘We tell our customers that the quality of the image depends upon three elements: the lighting, the lens and the camera. If you underestimate the quality required by any element of the system then you will not get a good result. If you choose very good lighting and a good camera, but not such a good lens, then you will not get a good output; the same is true for the other two elements. So we tell our customers that if they want the very best picture quality then they need to select high-performance elements.

‘We have found that the machine vision market in Europe is growing at a very healthy rate. Labour rates in Europe are very high and the European manufacturers are looking for opportunities to replace their workers with machines. I think this will continue for a while.’

Wada says that the secret of making a good lens is to start with the highest quality raw materials. The eventual quality also depends upon the design of the lens and the quality of its coatings but the most important thing is to measure and monitor the quality on the production line. Tamron has opened production facilities in China for its consumer products, but the machine vision lenses are all made in Japan, where there is a much longer history of quality assurance.

He says: ‘We buy in the glass, but we do the whole process from the grinding of the raw materials to the final quality checks. Some of our competitors outsource parts of the process, so they cannot control the quality 100 per cent. They still produce good lenses, but it is more difficult to guarantee the quality throughout. Although our headquarters is in Tokyo, our factories are more than 400km away in the north of Japan, where the humidity is much lower.

‘Optical design is also very important and we have about 20 people working on new developments in optical design. It is impossible to make a 100 per cent perfect lens, because of the physics, so we are always having to compromise. We are also always trying to reduce costs. We always ask our customers which part of the specification is most important to them, and we make sure we do not compromise on that. For machine vision customers, the most important thing is to minimise distortion and maximise contrast. Resolution is also becoming more important as people start using Megapixel sensors. Image size is getting bigger and bigger, because the CCD sensors themselves are getting bigger. When people used very low-resolution cameras the quality of the lens was not too important, but with greater resolution given by Megapixel cameras, the quality of the lens is now very important to our customers.

‘Most industrial cameras are used in factory environments, maybe on the end of robot arms. So they have to be able to withstand the vibration. It is very important that the body of the lens is made in a way that can withstand the environment in which it is going to be used.’

Tamron works closely with sensor manufacturers, as the two have to work hand in hand. Sony is one of its largest shareholders and there is a close working relationship. Clearly if Sony if going to develop a new form factor for CCD sensors, it will not sell many unless the lens manufacturers are also releasing compatible products at the same time.

Wada says: ‘Sony has just released a sensor that is between 2/3-inch and 1/2-inch, and the market has decided that this will be the standard. We are developing lenses with this size, so they can be incorporated into cameras.’

The Tamron range covers the most popular sensor sizes and focal lengths from 5.5mm to 75mm. The lenses are standardised so that the same filters can be used. The Megapixel lenses have a minimum optical distance of 15cm, which means it can fit into very tight spaces and does not need an extension ring. In addition, the distortion of about -0.05 per cent makes the picture quality very close to the human eye, which Wada says is extremely important in pattern checking and image processing applications. It also has an F-mount range for large image size cameras, such as line scan cameras and specialised applications.

Wada says that he has received a lot of enquiries for lenses to work with one-inch or 1.2-inch sensors. He says: ‘In a lot of factory automation applications with linescan cameras, you need these larger image sizes – either because they need more detailed information or to give an increased throughput.

‘At the moment most of the interest is in standard products, because with small volumes it can be very expensive to make a special lens. But in the future I think we will need to look at OEM development for certain customers.’

Wada says that price is a big issue to camera manufacturers, because there are so many camera manufacturers and low-end cameras are coming onto the market from countries like China. This has put pressure on the lens manufacturers, but at the moment the quality end of the market is largely dominated by Japanese companies. Chinese and Korean competitors are not yet able to reach the high quality standards demanded for high-end applications.

He says: ‘We have price competition between the Japanese companies, but we are also able to compete on other issues like quality and features. But I think in the future the quality of lenses from places like China is going to improve and start coming onto the European market; there will be a price war. We have to think about how we are going to differentiate our products from now on. We are confident in our quality, but it is very difficult sometimes to explain to our customers how different we are. We already have a factory in China, but it is not making machine vision lenses. At the moment the quantity is very low, but the factory is 100 per cent owned by Tamron, rather than being a joint venture. In the future it may be possible to transfer our manufacturing to China, while maintaining the high quality standards of our Japanese factory. We have Japanese engineers in our China facility, constantly training people. I am sure we will always be able to compete.’

As well as machine vision Wada is looking to expand into the area between CCTV and machine vision, such as traffic management systems and number plate recognition, which is a fast-growing market in Europe. He believes that there is growing recognition that improving the quality of the image can have a great impact on the usefulness of these systems.

He says: ‘Customers always blame the camera if they cannot get the image that they want, but in fact the lens is where you start. No camera can produce a clear image if it does not start with a good lens.’

Since Wada arrived in Europe, he has been trying to establish a network of distributors. Some are now established, but he is looking for more.

He says: ‘We are searching for distributors right now. Normally we have one or two distributors in each country, but we have only just started looking for them, so there are still some gaps. Germany is the largest market in Europe, so we have four distributors in Germany. Next are France and the UK, where we already have one distributor, but we are looking for more. We receive a lot of enquiries from Italy, so I think the market there is quite good.

‘We use distributors because we only have two people in the machine vision division in Europe, so we would not be able to provide good service without distributors. We are concentrating our service to those distributors, making it easier for them to sell by providing information and marketing materials. We would be delighted if those distributors only sold Tamron, but with the bigger companies they want to represent our competitors too. Pentax is very strong in Europe and many of the largest companies are using Pentax. But we find that when people get to test the Tamron range, we get a lot of people switching. Two years ago we were number three in the market and today I think we are now number two to Pentax.’

‘The machine vision market has a very long decision cycle with a lot of discussion and testing, so it is important from my perspective to support that process.’ Wada says that the security and automotive markets have huge potential, and in the future there may have to be a special division to deal with them. In particular the automotive industry has extremely high quality standards, because people’s lives can depend on the vision system used by a car. He says this makes it a very difficult industry to break into and will require considerable investment.