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Pioneering new applications with high-efficiency IREDs

Added unique value thanks to optical technology developed for automotive applications

Stanley Electric is deploying various LED devices covering a wide range of wavelengths.
The company is attracting attention with the newly released "high-efficiency high-power IREDs".
Stanley Electric achieved the highest luminous efficiency in the industry thanks to its diverse know-how, combined with optical technology developed for automotive applications, in order to create unique features.
These features contribute to rationalization of design and enhancement of functions in existing IRED applied equipment, such as security cameras, and at the same time contributes to the development of new applications such as automotive safety systems.

Seitaro Kondo

Seitaro Kondo

Stanley Electric Co., Ltd.
Optoelectronic Device Division, Sales Department III General Manager

Stanley Electric, which has consistently worked on light technology since its foundation in 1920, has been developing LEDs (Light Emitting Diodes) since the 1960's. In recent years, LED applications such as lighting for domestic and automotive use spread rapidly; the company pioneers the market for visible light LEDs. Stanley Electric is also actively developing UV LEDs and IREDs, and provide a variety of LED products covering a wide range of light wavelengths.

Stanley Electric has introduced ambitious products into the market one after another in each of the three major wavelength ranges: ultraviolet light, visible light, and infrared light (see enclosed article). In the IR range, the company is focusing on high-efficiency, high-power IREDs. Stanley Electric's latest products were showcased at "CEATEC JAPAN 2017", the large-scale IT and electronics exhibition held on 3-6th October 2017; demonstration units deploying IREDs were also exhibited at the same time, attracting the attention of many visitors.

Developed for new automotive applications

An IRED is a light-emitting device whose peak wavelength exceeds 780 nm. IR communication systems such as household electric appliances, remote controls, etc., are already in use in a wide range of applications. Among these IREDs, demand for high-output IREDs has recently increased. They are aimed at nighttime security lighting systems such as security cameras, light sources of TOF (Time Of Flight) type distance image sensors, etc. More recently, IREDs are expected to be applied to driver monitoring systems (DMS) that detect the driver's conditions (such as dozing), sensors for automatic driving systems, etc. Stanley Electric developed high-efficiency high-power IREDs aimed at existing applications as well as more advanced applications (Fig. 1). There are two types of devices emitting at 855 nm and 945 nm, with narrow directivity ― 60 degrees type (M□N1105MS) - and wide directivity - 120 degrees type (M□N1106MS). "Demands for the security field will increase towards the Tokyo Olympic Games in 2020. In addition to automotive systems such as DMS, new applications such as disaster prevention cameras that protect civic life from abnormal weather, and light sources for biometric authentication systems are expected to be in high demand" (Mr. Seitaro Kondo, Stanley Electric, Optoelectronic Device Division, Sales Department III).

Fig.1: High-efficiency high-power IREDs

High-efficiency high-power IREDs
(Left) Narrow directivity type 「M□N1105MS」 (Right) Wide directivity type「M□N1106MS」

Increased freedom in equipment design

A major feature of Stanley Electric's newly released high-efficiency high-power IREDs is that both 855 nm and 945 nm devices achieve more than 610 mW/W (radiant flux / input power), and it is the highest luminous efficiency in the IR field. Therefore, high output can be obtained with the same current as the conventional one. "We have newly developed an LED with low forward voltage (Vf) and capable of high power output" (Mr. Kondo). In the market, to increase light output there are many devices whose forward voltage value is equivalent as two LED dies. However, such a device is disadvantageous to suppressing power consumption. Therefore, in Stanley Electric's high-efficiency high-power IREDs, the forward voltage value is equivalent to one LED die and die materials and structure are optimized multilaterally, aiming for high efficiency. Furthermore, using the optical design know-how and packaging technology cultivated with automotive LEDs, Stanley Electric also optimized the optical lenses mounted on the LEDs' top surface, thereby maximizing the efficiency of light emitted from the die.

High-efficiency high-power IREDs with such features bring many advantages to equipment designers. "For example, we can dramatically reduce the number of IREDs built into security cameras. In concrete terms, the same brightness as the light source made up of 36 conventional through-hole IREDs can be obtained with just one LED. The same power consumption can be achieved with 3 LEDs, and it can illuminate brightly and widely" (Mr. Kondo) (Fig. 2). In other words, by adopting a high-efficiency high-power IR LED, not only is it possible to reduce the cost by decreasing the number of parts, but also to reduce the size of the entire unit by making the light source smaller.

Another advantage not to be overlooked is that high-efficiency high-power IREDs can suppress generation of heat during lighting, by increasing efficiency (Fig. 3). In addition to contributing to reducing substrate temperature, simplification of the heat dissipation mechanism results in cost reduction and high packaging density. The newly released high efficiency high-power IRED is a newly designed compact package (3.8 mm long × 3.8 mm wide × 2.1 to 2.8 mm high), using ceramic with high heat dissipation properties and Cu (copper), adopted to further improve heat dissipation. "It is advantageous in securing reliability of the final unit, since the limitations due to heat will be low and the design degree of freedom will increase" (Mr. Kondo).

Fig. 2: Contributing to equipment downsizing

Contributing to equipment downsizing
(Left) Example of security camera employing conventional through-hole IREDs (36 pcs)
(Right) Example of security camera employing high-efficiency high-power IREDs (3 pcs)

Fig. 3: Reduced heat compared to conventional products

Reduced heat compared to conventional products

Development of IRED floodlights

Stanley Electric provides electronic devices such as LEDs, as well as applied products such as various modules and equipment using electronic devices. The company is also developing equipment mounting high-efficiency high-power IREDs. At "CEATEC JAPAN 2017", Stanley Electric showcased a sample exhibit of IRED floodlight for long distance security cameras, equipped with high-efficiency high-power IREDs (Fig. 4). It deploys IREDs and optical lenses mounted on a small casing with an external size of 55 mm × 55 mm × 60 mm. The optical lens design has been optimized, making full use of advanced simulation technology. The directional half-angle of 3 degrees and the light distribution angle are throttled down a lot, so that IR light reaches far (Fig. 5). Using this floodlight, it is possible to capture an object 100 meters ahead.

Stanley Electric, which has commercialized IREDs featuring characteristics that make it distinctive from competitors, will create a new market for IREDs, making full use of LED dies and optical designs that have been proven to a great extent in automotive applications.

Fig. 4: Emitter with high-efficiency high-power IREDs

Emitter with high-efficiency high-power IREDs

Fig. 5: Optical design simulation

Optical design simulation

Awards won by Stanley Electric for its Ultra-Narrow Light Angle Type LED Floodlight

The Ultra-Narrow Light Angle Type LED Floodlight developed by Stanley Electric, boasting numerous adoptions in automotive visible light LED range such as headlamps, turn lamps, tail lamps etc., has received high evaluation in a wide range of industries (Fig. A). This LED floodlight achieved an extremely narrow light distribution angle of 2.5 degrees by making full use of the optical design technology cultivated through the development of automotive headlamps. Stanley Electric enhanced power efficiency of lighting equipment by improving luminous efficiency.

The emitter was installed in November 2016 to light up Niagara Falls, the world-famous tourist attraction located on the border between the United States (New York State) and Canada (Ontario State) (Fig. B). In this facility, red, blue, green, white light is irradiated towards the waterfall from three emitters at a distance of 250 - 600 m. We used to use lighting equipment deploying 21 light emitters that use 4 kW xenon short arc ball as a light source. It was replaced with 1,400 LED emitters (red, blue, green, and white: 350 pcs each). Despite the fact that the scale of the facility has increased drastically, the power consumption of the entire facility has been reduced by approximately 60%, from 126 kW to 54 kW. Colors were conventionally expressed by combining four color filters; on the other hand, this LED floodlight is capable of irradiating more than 16.77 million colors by multiplying and adjusting the four colors; the effect has improved dramatically. These illuminations (designed by Salex, Inc. and M & B Lighting, Inc.) won the "Award of Excellence" at the IES Illumination Awards 2017, presided over by the Illuminating Engineering Society of North America (IES).

In addition, Stanley Electric has also won two awards at "CEATEC JAPAN 2017" held in October 2017. One is the CEATEC award that evaluates innovation from an academic and technical point of view, broadening the future of the market, - the "Semi-Grand Prix of Home & Lifestyle Innovation Category" (Fig. C). The other is the "US Media Panel Innovation Award". An advisory panel of US journalists related to IoT selected Stanley Electric from among all "CEATEC JAPAN 2017" exhibits, technologies, products and services of high influence to future markets.

Ultra-Narrow Light Angle Type LED Floodlight

Fig. A:
Ultra-Narrow Light Angle Type LED Floodlight

Ultra-Narrow Light Angle Type LED Floodlight

Fig. B:
Niagara Falls illuminated with Ultra-Narrow Light Angle Type LED Floodlights

Fig. C

Awards won at

Home & Lifestyle Innovation Category
Semi-Grand Prix

"US Media Panel Innovation Award"
Components Category