Gratings mainly include slit gratings and cylindrical gratings.
1. Slit grating, that is, line grating, is the earliest and more mature grating, and its imaging principle is that of pinhole imaging. Because this kind of grating is relatively easy to make and the technical difficulty is not high, very beautiful large-scale slit grating three-dimensional light box advertisements appeared more than ten years ago. Nowadays, some three-dimensional production companies are still willing to use slit grating three-dimensional light boxes to participate in exhibitions. The effect is good, but the slit grating three-dimensional light boxes have the following defects: the light transmittance is only 20-30%, not environmentally friendly, not energy-saving, and the lighting consumes a lot of energy. It is large, generates a lot of heat, and is not bright enough for outdoor use. It is only suitable for indoor use.
2. There are many types of cylindrical gratings, mainly including plates and mold materials. The imaging principle is the refraction and reflection imaging principle of a curved lens. Lenticular gratings have great potential and can be used indoors and outdoors with or without lights, and their market penetration is expanding. Grating membranes were once popular because of their price competitiveness. However, due to the gradual decline in the price of lenticular grating plates, the need for membrane materials to be pasted and the technology that needs to be improved, their competitiveness has not become outstanding.
Gratings can also be divided into:
1. Transmission grating;
2. Reflection grating.
An optical device composed of a large number of parallel slits of equal width and equal spacing is called a grating. Commonly used gratings are made by carving a large number of parallel notches on a glass sheet. The notches are opaque parts, and the smooth part between the two notches is light-transmitting, equivalent to a slit. The refined grating is engraved with thousands or even tens of thousands of notches within a width of 1cm. This kind of grating that uses the diffraction of transmitted light is called a transmission grating. There are also gratings that use the diffraction of reflected light between two scratches. For example, many parallel scratches are carved on a surface coated with a metal layer. The smooth metal between the two scratches The surface can reflect light, and this grating is called a reflection grating.
Reference: Baidu Encyclopedia: /link?url=8rrPaFYFK3nVdNC-GVxO_UjOlztukfeLuG5vm1DGD3MThuamO0rTMHoWJ_9IgVhN34LExp9H1yEROydE7Koisq#5