DLP technology is a kind of micro electro mechanical system (MEMS) technology that uses digital micromirror device (DMD) to adjust light. Each micromirror of DMD represents a pixel on the screen and is adjusted independently to keep pace with the color sequence illumination, thus creating an amazing display effect. DLP technology supports the display of many products around the world, from digital cinema projectors to smart phones. In 2014, a new DLP Pico chipset based on the breakthrough micromirror technology came out, which is called DLP Trp. The pixel spacing of DLP Trp chipset is only 5.4 μ m, the deflection angle is increased to 17 degrees, the resolution is higher, the power consumption is lower, and the image processing function is enhanced. At the same time, the first-class optical efficiency of DLP technology is still maintained (Fig. 1). Ti Trp chipset is very suitable for any display system that requires high resolution and high brightness with low power consumption in compact size.
There are several key advantages of near eye display using DLP technology
High optical efficiency – DLP technology provides very high optical efficiency. The micro aluminum micro mirror can reflect most of the incident light and create a brighter near eye display with lower illumination power.
Polarization independent – DLP technology can be used with any light source including LED, laser, laser phosphor and bulb. If non polarized light sources such as LED are used, the optical system based on DLP has high efficiency, because it does not need polarization conversion and can make up for the loss.
The advantage of optical efficiency makes DLP technology especially suitable for higher brightness near eye display applications, such as perspective and larger field of view applications. With the increase of brightness, the power advantage of DLP system is more obvious. DLP Pico chipset is equipped with small and efficient controller and PMIC / LED driver supporting integrated reliable system, which has the characteristics of small size and low power consumption. The controller is only 7mm × 7mm, and the PMIC is only 3.4mm × 3.2mm. The typical power consumption of DMD and controller combination is 150MW ~ 300MW, depending on the array size and resolution. Figure 11 shows a typical system block diagram of a near eye display application using DLP technology solutions.
Figure 10: small circuit board design example
Figure 11: example of system block diagram
DLP controller communicates with front-end processor through I2C and receives 24 bit RGB video data through parallel interface. The front-end processor uses proj_ On signal controls the power on and power off of DLP system. The PMIC / LED driver provides all necessary power for the controller and DMD, while the integrated LED driver provides configurable RGB LED current.
The chipsets in Table 2 are ideal for near eye display applications.
Table 2, chipsets for near eye displays
DLP technology is one of the most mature display technologies in the market. Millions of DLP chips have been sold, and DLP cinema is the technology used by nearly 90% of the digital cinema screens in the world. DLP chipset for near eye display adopts the same core technology and converts it into a micro display, which can create cinema level image quality in almost any near eye display application.