What is the transmittance reflectance of glass？

According to the law of conservation of energy, there exists the following relationship between the transmittance (T), reflectance (R), and absorption (A) of light passing through any medium:

T+R+A=1

To achieve high transmittance, it is necessary to reduce the reflection of light on the glass surface, absorption and scattering losses in the glass.

1. The reflectance increases with the increase of incident angle, but the change in reflectance with incident angle is not significant when the incident angle is less than 40 degrees, and when the incident angle is greater than 70 degrees. The reflectivity increases sharply with the increase of incident angle. The reflectivity also increases with the difference in refractive index between the two media.

For the interface between glass and air, the refractive index n0 of air is 1, and the refractive index n1 of glass is 1.52. The refractive index is fixed, so the main factor affecting reflection is the size of the incident angle.

2. Light absorption loss: Generally, the darker the color, the smaller its transparency coefficient. To reduce the light absorption loss of glass, lighter colored glass can be selected for use. In addition, the transmission loss of glass decreases exponentially with the thickness of the glass, and it can be seen that the smaller the thickness, the smaller the transmission loss.

3. Scattering loss: The scattering loss of glass mainly occurs in composite glass. Due to the presence of some particles inside the glass that can change the direction of light, some light cannot be imaged and loses its function. The scattering loss of light depends on the size of the scattering point. When the size of the scattering point is of the same order of magnitude as the wavelength of the incident light wave, the scattering is greater. When the diameter of the particle is about half of the wavelength of the incident light, the scattering reaches a greater value.

For agricultural production system materials, when there are particles inside, observing the object through glass due to the forward light scattering caused by the object being on the same side as the light source will result in surface haze, which will cause a loss of contrast and affect the clarity of observation through glass.

4. Other factors that affect transmittance: Different surface smoothness of glass screens has a significant impact on transmittance. The transmittance of different parts of the same glass screen may vary by more than 1% when measured by hand surface conditions. Different glass screens are more likely to have differences. The smoothness should mainly affect the reflectivity.

Impurities inherent in glass raw materials can also affect transmittance, such as ferric oxide, which should be due to the impact on absorption rate.

How to reduce the reflectivity of glass materials？

Surface treatment can be applied to glass, such as the principle of low reflective glass.

Low reflective glass, also known as anti reflective glass or non reflective glass, anti glare glass. It is a type of glass that undergoes special surface treatment. The principle is to perform a single-sided or double-sided sanding and polishing process on excellent glass. Make it have a lower reflectivity compared to ordinary glass, reducing the reflectivity of light to below 1%, thereby reducing the interference of ambient light, improving the clarity and energy of the image, reducing screen reflection, and making the image clearer and more realistic. Provide viewers with better visual effects.

Low reflective glass reduces the reflectivity of the glass surface to below 2%, with a light transmittance of over 80% and a glossiness of over 60%.