LED is expected to be used as a next- generation light source to　replace conventional light bulbs and fluorescent lamps.

This trend is significant not only in the field of general lighting, but also in the field of automotive lighting.

In this article, we will explain what categories will be utilized and what developments will be made in the future will the indoor LED for automotive use.

We will compare with conventional light sources, we will explain what LED light sources are, their characteristics and merit.

What is an advantage over conventional light bulbs?

Light bulbs were the primary lights for automobiles before the advent of LED.

However, it is not perfect in terms of visibility, color tone, and short life.

Therefore, a light source that can be replaced with a light bulb has been in demand.

As advantages of LED over conventional light bulbs,

・Enviromental Considerations

・Brightness

Two are listed.

Eco-friendly environment

Automobile industries have been considering about environmental issues.

We have been practicing “eco-friendly “initiatives such as exhaust gas reguration and energy conservation.

Of course, both exterior and interior lighting for automotive are also eco-friendly products.

LED are being used not only to room lamps, but also instrumental panels and to the entire interior space.

LED consume 85% less power than light bulbs, and since the light source itself emits less heat, it emits that much less CO2.

It also has the advantage of long life.

Assuming that the rated life is 40,000 hours, even if the light is turned on for 10 hours a day, it can be used for more than 10 years.

If you purchase a new car, it is not necessary to replace the light source even when the timing of the next replacement is reached.

Bright and easy to see

Not only customers who like the attractive styling and exterior, but there are also those who value the indoor environment and design.

Especially when test-driving, the driver’s curiosity will be satisfied not only the ride comfort and handling but also the visibility of the meters.

Bright and easy to see, colorful colored instrument panels attract your eyes, and beauty stands out at night.

It is also a characteristic of LEDs to be able to enjoy such gradation.

LED is used not only in the area around the instrument panel, but also as a light source for various types of switch and control panels around the air conditioner.

Especially in the case of eco-cars, power saving in various electric components increase in the driving distance, which is a major appeal point.

LED with high flexibility in design

LED’s technological innovations have also brought major changes to automotive LED.

The point is that the degree of flexibility has increased for designs.

Multiple LED are needed to achieve the required brightness because conventional LED have low brightness per unit.

However, the improvement of luminous efficiency of LED chips has led to the development of LED with higher brightness and less mounting space.
Therefore, power saving is possible.

Since fewer LED are used, there is more flexible in design, and the advantage is that costs can be kept low.

Also, as LED themselves become more varied in terms of brightness, light distribution, and color tone, they can be used in a variety of design

What Is the Problem of Automotive LED?

LED are not almighty, but they save power, last longer, and can be designed with flexibility. Problems with quality and cost cannot be avoided.

Uneven brightness and color

Many of the control switches are linked to the small lamps and transmit light from the rear. The design surface which transmitted through may change the brightness and color tone whether too close or not. When it’s too far, use LEDs with higher brightness or adjust the brightness using a condenser lens, light guide.

When it’s too close, a diffusion lens (diffuser plate ・ filter) is used, but when light passes through it, color tones may change or color unevenness may occur.

To prevent this from occuring , a thorough evaluation of brightness and color is necessary during the design process.

On the other hand, variation in brightness and color may occur depending on the current. General LED are designed for a current of about 10 to 20 mA. If current below 5 mA is applied, the amount of light emitted may vary greatly or not light up.

The current should also be assumed and designed.

In addition, we have to recognize the differences in quality between each manufacturers.

Headlights are being converted to LED.
However, it is not generally true that LEDs are universally used in interior environments.　

With the ongoing technological innovation of LEDs, it is not wrong to say that LEDs for automotive applications have unlimited possibilities.

Reliability is required for automotive LEDs not only for exterior lighting such as headlamps and tail lamps.

The same reliability is required for interior lighting used in instrument panels, room lamps, control panels, etc.　The performance of a LED is greatly affected by the environmental conditions.

Light output tends to decrease at high temperatures, so it is necessary to meet photometric performance requirements even in harsh temperature environments.

It can be said that the use of reliable LED is essential.

Along with LEDs, which are attracting attention as the next generation of in-vehicle lighting, there are other technologies that are also attracting attention.

That is “laser optical fiber lighting”.

Since this technology can emit colorful light from fibers less than 1 mm in diameter, it is expected to play a role in room lamps and indirect lighting.

By improving the texture of the interior, we can create a luxury space with a more luxurious feeling, but it is likely that the interior will be categorized from LED.

This is because there are still many issues to be addressed in terms of safety, since the absolute light intensity is not as high as that of LEDs, and strong light leaks out if the fiber is damaged.

Perhaps various improvements will be made in the future.

Nichia Corporation is the first name that comes to mind as Japanese top leader in the field of LED.

Nichia has earned a reputation for introducing high value-added products in a variety of fields, including the development of white LEDs that combine LEDs and phosphors.

In addition, Nichia licensed to Asahi Rubber and Citizen Electronics, etc., and those who have licencing agreements are expanding their markets with their own packaging technology.

Nichia’s strength that all of its production process are in-house.

This allows them to centralize quality control and supply high quality products.

Nichia’s technology also meets diversifying demands.

This will enable to achieve the brightness and color required by the user in detail, resulting in satisfactory.

Nichia’s LED are backed by high tech and strict quality-control technologies. At Asahi Rubber, which is licensed, we are developing markets in the field of automobile lights.

That is called “ASA COLOR LED.”

A silicone rubber cap containing phosphor is covered on top of blue LED to meet the demand for a wide variety of colors.

There are more than 10,000 color variations.

There are many problems that can occur in the design stages.

Isn’t it a challenge to explore solutions, such as lack of desired colors, brightness and color variation, and cost problem?

Asahi Rubber has an extensive track record of delivery to the automotive industry, and we also accept customs as desired.

If you are in trouble, please feel free to consult with us.

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