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Strengthening LED business with technology developed for automotive applications

Pioneering new markets while contributing to society

Stanley Electric, leader in optics technology, has embarked on the development of a new LED market.
In addition to LEDs in the visible light spectrum, boasting many achievements for automotive applications, Stanley Electric has introduced ultraviolet LEDs and infrared LEDs, which can perform various functions. The company is planning to increase market share by proactively developing products intended for applications that contribute to social development. Mr. Hiroyuki Enomoto, Executive Officer, spoke about the company's efforts and approach to LED development.

Hiroyuki Enomoto

Stanley Electric Co., Ltd.
Executive Officer

An LED (Light Emitting Diode) is a semiconductor light source. When white LEDs began to appear on the market around 2000, they gradually became used as light sources for various equipment such as household lighting appliances, automotive headlights, mobile phones, LCD televisions, etc. They brought innovative evolution. LEDs are extremely important devices to us.

Our company has developed starting with the manufacture and sale of automotive light bulbs and special light bulbs that started soon after the foundation in 1920. From the beginning we have consistently worked on light technology. Following our corporate philosophy called "Stanley Group Vision", we are striving to create social value by exploring the five values of light (Fig. 1). In other words, we are developing our business based on the "5 Values of Light": "CREATING" (creating light), "RECOGNIZING" (sensing and recognizing with light), "INFORMING" (processing information with light), "ENERGIZING" (harnessing light's energy), "EXPRESSING" (producing feeling with light). There are three main pillars of our business; one is the "Automotive Equipment business" centering on headlights; another one is the "Components business", that develops various electronic devices; the last one is the "Electric Applications business" that provides equipment and modules using electronic components.

LED technology is the key to our business development. We have been developing LEDs since the 1960's, and we have already accumulated solid technologies and know-how. In recent years, with the rapid expansion of LED applications, we have been able to further develop our business. It was visible light LEDs that became the driving force, but our idea is to expand our product portfolio of UV LEDs and IREDs, to further develop new markets by bringing innovation in various fields.

Fig. 1: Stanley Electric's "5 Values of Light"

Stanley Electric's 5 Values of Light

Making the best use of the various functions of light
Pioneering new applications

LEDs in the visible light spectrum are already widely used as light sources for automotive headlamps, lighting appliances, indicators, traffic lights and so on. LEDs that emit UV light with a wavelength of 400 nm or less, or IR light with a wavelength of 780 nm or more can be applied also to other purposes (Fig. 2). Light in these wavelength ranges provides various functions. For example, UV light can sterilize and deodorize; it can be used to cure certain materials which react to UV light, and also for applications such as bonding and sealing. On the other hand, IR light can be used for sensing and night vision.

Several lamps that emit UV light and IR light are already on the market, but LEDs are expected to have excelling features such as small size and low power consumption that greatly influence device development. Just as when bulbs and fluorescent lights (which used to be used as light sources for lighting equipment) were replaced by LEDs, this should bring innovative evolution to many devices.

Fig. 2: Expand wavelength range coverage to exploit new applications

								Seeking new functions for non-visible light applications
								UV light spectrum
								Resin curing

								Visible light spectrum
								General lighting
								Traffic lights

								IR light spectrum
								Various sensors
								Automotive cameras

Focus on water sterilization systems
Contributing to society by solving problems

There are many applications where LEDs not in the visible light range can be deployed, but one that is receiving close attention is water sterilization. Light with a wavelength of 100 nm to 280 nm ― called "Deep-UV" ― exerts a sterilizing function. This function is used for water purification.

Demand for water purification systems is going to increase worldwide in the future. Water shortage problems and water pollution are becoming increasingly serious all over the world, along with population growth and the economic development of emerging countries. Currently, the main devices used as a Deep-UV light source are UV lamps such as cold cathodes and hot cathodes. It is said that the market for UV lamps for sterilization will be 160 billion yen by 2020.

Actually, LEDs are becoming advantageous in this market. UV lamps contain mercury, which makes them hard to use in the future. Since the Minamata Treaty (which aims to protect human health and the environment from mercury) came into effect there is a possibility that UV lamps for sterilization may be subject to regulations in the future. In that case, I think that the demand for Deep-UV LEDs as an alternative light source will increase.

We intend to pioneer this market by developing LEDs with superior functions and performance ahead of competitors. Technologies refined through the development of automotive LEDs, boasting a number of proven achievements, will demonstrate their power.

Our Deep-UV LEDs boast the highest output power in the field (50 mW), emitting at 265 nm, which already has high bactericidal effect; in May 2017 we were the first to announce the establishment of such Deep-UV LEDs mass production technology (Fig. 3). We plan to launch Deep-UV LEDs mass production from December 2017. We are planning to sell not only LED devices, but also a water sterilization module that mounts Deep-UV LEDs with superior sterilizing capability. We believe that we can contribute to the development of society by actively developing these devices, to encourage the spread of water sterilization systems that minimize environmental burden. Please, pay attention to our future developments.

Fig. 3: High-power Deep-UV LED emitting at 265 nm, with high bactericidal effect