The principle of LCOS optomechanics, the principle of light emission of LCOS
LCOS (Liquid Crystal on Silicon) is a new type of reflective micro LCD projection technology. It uses a CMOS integrated circuit chip coated with liquid crystal silicon as the substrate of the reflective LCD. It is polished with advanced technology and coated with aluminum as a mirror. A CMOS substrate is formed, and then the CMOS substrate is bonded to a glass substrate containing transparent electrodes, and then injected into a liquid crystal package. LCOS puts the control circuit behind the display device, which can improve the light transmittance, so as to achieve greater light output and higher resolution. The following figure is a cross-sectional analysis diagram of the LCOS liquid crystal packaging level: LCOS can also be regarded as a type of LCD. The traditional LCD is made on a glass substrate, and LCOS is made on a silicon wafer. The former usually uses the transmissive projection method, the light utilization efficiency is only about 3%, and the resolution is not easy to improve; LCOS uses the reflective projection, the light utilization efficiency can reach more than 80%, and its biggest advantage is that it can be widely used at present 3. Cheap CMOS production technology to produce without additional investment, and with the rapid miniaturization of semiconductor manufacturing process, gradually improve the resolution. On the other hand, high-temperature polysilicon LCD requires separate investment in equipment, and it belongs to a special process, so the cost is not easy to reduce. The structure of the LCOS panel is somewhat similar to that of TFT LCD. Spacer is distributed between the upper and lower two layers of substrates for isolation, and then filled with liquid crystal to form a light valve between the substrates. The circuit switch is used to drive the rotation of liquid crystal molecules to determine the picture Light and dark. The upper substrate of the LCOS panel is ITO conductive glass, and the lower substrate is a CMOS substrate coated with liquid crystal silicon. The biggest feature of the LCOS panel is that the material of the lower substrate is single crystal silicon, so it has good electron mobility and single crystal silicon can be formed Compared with the existing LCD and DLP projection panels, LCOS is a new type of projection technology that can easily achieve high resolution. LCoS TV sets need to go through several steps to produce pictures. This process involves a high-intensity light bulb, a series of reflectors and micro-devices arranged in a cube, a prism and a projection lens. Here is what happened in the whole process: 1. The bulb produces a white light. Cold Plate Copper Tube Heat Sink Copper Pipe Heat Sink,Cooling Plate Heat Sink,Extruded Aluminum Heatsink,Cold Plate Copper Tube Heat Sink Dongguan Formal Precision Metal Parts Co,. Ltd , https://www.formalmetal.com
cover glass: protective glass
ITO Alignment layer: ITO common electrode layer [E'lainmEnt]
Lc material: liquid crystal substance (filling substance)
spacers Spacer plating (for aluminum)
CMOS substrate: CMOS substrate
2. The light beam passes through a condenser lens (responsible for focusing and aligning the light). It also passes through a filter (only visible light is allowed to pass through), which protects other components from damage.
3. This white light is decomposed into red, green and blue light in one of two ways:
1. The beam passes through a polarizing beam splitter (PBS), which splits the light into three beams, which pass through filters that add red, green, and blue, respectively.
2. The light beam passes through a series of dichroic mirrors. These dichroic mirrors can reflect light of certain wavelengths while allowing the rest of the light to pass through. For example, a dichroic mirror can separate red light from white light, leaving blue and green light, while another dichroic mirror can separate green light and leave only blue light.
4. The color beam just generated is in contact with one of the three LCoS microdevices at the same time-they correspond to red light, green light and blue light respectively. In the next section, we will introduce these devices.
5. The light reflected by these micro devices passes through a prism, which can combine the light.
6. The prisms then project the light rays (they now produce a full-color image) into a projection lens, which magnifies the image and displays it on the screen.