Tint Meter | Automobile Glass Light Transmittance Measurement

Due to the hardness and corrosion resistanc of glass, we will use a lot of glass in daily life and social production. The materials used to make glass are different and the properties are different, so they will produce different light transmittances. So they are used in different industries. We believe you will also encounter problems with the transmittance of automotive glass, including influencing factors, how to measure, etc. This article will give you a detailed answer.
       When light enters the glass, there will be three kinds of performance, namely reflection, absorption and projection, the sum of the three is equal to 100%. Among them, the phenomenon of light passing through glass is called "transmission", which is expressed in light transmittance. The calculation method is: outgoing light flux / incident light flux * 100% = transmittance. The light transmittance of ordinary glass is above 80%. In actual production and application, some glasses even require higher light transmittance.

1. Factors affecting the transmittance of automotive glass:

(1) The influence of raw materials and charge

Most raw materials for producing glass come from mined minerals or chemical raw materials produced by chemical plants. Among them, the high content of impurities in mineral raw materials will reduce the light transmittance of glass. For example, ferric oxide is one of them. Most chemical raw materials are pure and have few impurities, so they will not affect the light transmittance of glass. For the same kind of glass, we can use the tint meter to test the light transmittance and determine whether the raw material is mineral or chemical material.

(2) Glass frit

Glass products are prone to some defects during forming, such as cold lines, pits, etc. These defects will reduce the light transmittance of the glass. In addition, bubbles and stripes on the glass frit will affect the amount of light incident. When the fringe distribution is relatively dense, the light transmittance will be greatly reduced.

(3) The influence of color and thickness on glass

In general, the darker the color, especially the black, gray, red and other colors, the greater the light absorption loss, the smaller the light transmittance of the glass. To avoid the light absorption loss of the glass, it is necessary to use light color on glass. In addition, the higher the thickness, the lower the light transmittance of the glass. In the industrial production of TVs, in order to reduce the influence of thickness on light transmittance, the glass is usually frosted on one or both sides. This treatment can reduce the reflectivity of light and effectively reduce the interference of ambient light on the glass. The audience can get a clear picture image, the visual effect is better.

(4) The effect of surface finish on glass

Different surface finish of the glass screen will also affect the transmittance of the car glass. Different parts of the same glass screen have different conditions. The measured light transmittance may sometimes differ by more than 1%.

2. How to detect the transmittance of automobile glass?

There is a calculation formula for light transmittance. But at this stage, due to the development of technology, instruments for quickly detecting the light transmittance of automobile glass have appeared. According to national regulations, the visible light transmittance of the front windshield is not allowed to be less than 70%. All window glass is not allowed to post mirror reflective sunshade film. Therefore, it is necessary for car owners to detect the light transmittance after attaching a reflective sunshade film, which is also necessary for car manufacturers.
       Generally speaking, to detect the transmittance of automotive glass, hazemeter or spectroscopic transmittance tester can be used. You can also consider using Linshang LS110 tint meter. LS110 tint meter adopts white light source conforming to the CIE photopic luminosity function. This tint meter also use the parallel light path design, the accuracy can reach ± 1%, which has been widely recognized and welcomed by the customers. The most important thing is that the operation method of the Linshang LS110 tint meter is relatively simple. The results can be accurately measured in a short time.