INTEGRATED MICRODISPLAY PROJECTION AND IMAGING SYSTEM
An integrated microdisplay projection and imaging system includes: a focus-adjustable lens system, a planar polarization beam splitter, a reflective polarization modulation imager and an imaging sensor with a post polarizer in orthogonal polarization orientation to the planar polarization beam splitter, as well as a lighting module. Placed on two separate sides of the planar polarization beam splitter, the reflective polarization modulation imager and the imaging sensor have substantially equal-length optical passes through the planar polarization beam splitter to the focus-adjustable lens system, and thus the focus-adjustable lens system provides a unified means for adjusting focus with both the reflective polarization modulation imager and the imaging sensor, relative to an external object such a projection screen or an imaging object.
1 . An integrated microdisplay projection and imaging system comprising:
a focus-adjustable lens system with a principal axis;
a planar polarization beam splitter configured facing the focus-adjustable lens system in a facing angle close to 45-degree with the principal axis;
a reflective polarization modulation imager configured on first side of and in a reflection angle close to 45-degree with the planar polarization beam splitter;
an imaging sensor configured on second side of and in an imaging angle close to 45-degree with the planar polarization beam splitter;
a lighting module inducing collimated illumination in an incident angle close to 45-degree with the planar polarization beam splitter;
wherein an optical pass distance for projection, measured from the reflective polarization modulation imager through the planar polarization beam splitter to the focus-adjustable lens system, is configured equal to an optical pass distance for imaging, from the imaging sensor through the planar polarization beam splitter to the focus-adjustable lens system.
2 . The system according to claim 1 , further comprising a post polarizer in orthogonal polarization orientation to the planar polarization beam splitter, configured between the planar polarization beam splitter and the imaging sensor.
3 . The system according to claim 1 , further comprising a pre polarizer in orthogonal polarization orientation to the planar polarization beam splitter, configured between the planar polarization beam splitter and the lighting module.
4 . The system according to claim 1 , wherein the reflective polarization modulation imager 300 is a liquid crystal on silicon microdisplay imager.
5 . The system according to claim 1 , wherein the reflective polarization modulation imager comprises a quarter wave retarder plate and a MEMS-based diffractive spatial light modulation imager configured in parallel in the imaging angle substantially close to 45-degree with the planar polarization beam splitter wherein the quarter wave retarder plate is placed between the diffractive spatial light modulation imager and the planar polarization beam splitter.
6 . The system according to claim 1 , wherein the focus-adjustable lens system further includes an aperture adjuster for adjusting light inductance for imaging through the focus-adjustable lens system eventually unto the imaging sensor and light inductance for projection through the focus-adjustable lens system from the reflective polarization modulation imager and the lighting module.
7 . The system according to claim 2 , wherein the post polarizer is integrated in a thin film configuration onto the imaging sensor.
8 . The system according to claim 7 , wherein the imaging sensor comprises:
a planar array of color filter elements; and
a planar array of photo sensing pixels optical aligned with the color filter elements, each photo sensing pixel comprising at least a photo diode on a semiconductor substrate.
9 . The system according to claim 8 , wherein the post polarizer is adherently fabricated onto the planar array of color filter elements.
10 . The system according to claim 8 , wherein the post polarizer is a wire grid polarizer made from elongated reflective metal strips fabricated between the planar array of color filter elements and the planar array of photo sensing pixels.