LCOS Optical Engine Architecture

Since LCOS technology is still in its infancy and there are no standard processes at present, many manufacturers have developed different LCOS optical engine architectures. More representative manufacturers include IBM, ColorQuad, Philip, Hologram,... Each kind of technology has its own advantages and disadvantages. Among these different technologies, it can be divided into two types: three-piece type and single-chip type. Details are as follows:

One: three-chip optical engine LCOS optical engine is currently based on three-chip, three-chip light source is divided into red, blue and green light through the prism, and then the beam is cast into three LCOS panels, respectively, The projected three-color images are converged by an optical system to form a color image. With respect to the IBM 4-Cube optical engine architecture designed by Nikon, since the three-piece LCOS optical engine requires not only three panels, but also a plurality of splitting and combining systems, it is larger and more expensive. Because it can achieve high optical efficiency and high image quality, it is mainly for high-end professional development. The main products are mainly JVC projectors, in addition to three-chip optics. The engine also includes the ColoRQuard architecture used by ColorLink, the Prism architecture of Philips, the Dichroic-PBS architecture for development, and the ColorCorner architecture for Unaxis.

Second, the monolithic optical engine monolithic Color Wheel optical engine uses the rapidly rotating ColorSwitch to form white light sequentially in red, blue, and green, and synchronizes the three primary colors with the red, blue, and green images generated by the driver. A color separation image is formed, and the characteristics of the persistence of the human visual system finally produce a color projection image in the human brain. Similar technologies include: Field Sequential Color by Displaytech, Scrolling Color-Rotating Prism Architecture by Philip, and Spatial Color-Hologram Architecture by JVC.

The biggest advantage of the monolithic type is that because the number of panels is only one, and the system architecture with split and combined light is relatively simple, it has more competitive advantages in terms of cost, and the space for optical engines is relatively small. However, currently there are some technical difficulties. For the Color Wheel, the white light is only 1/3 of the light source after the polarization, and the brightness is obviously reduced; in addition, the LCOS panel has to be fast on the red, blue, and green screens. Switching the synthetic image, so the panel response speed requirements are higher, making the production more difficult.