An image processing apparatus according to the present disclosure includes an illuminating section which sequentially irradiates an object with first and second illuminating light beams polarized in first and second directions. First and second polarization images are generated based on signals representing light transmitted through polarizers having the polarization transmission axis in respective directions that are parallel to, and intersect with, the first direction while the object is being irradiated with the first illuminating light beam, and third and fourth polarization images are generated based on signals representing light transmitted through polarizers having the polarization transmission axis in respective directions that are parallel to, and intersect with, the second direction while the object is being irradiated with the second illuminating light beam. A depressed object surface region is detected based on the first and second polarization images and/or the third and fourth polarization images.

An image display device is provided. The image display device includes a light source and a polarizer including a first polarizing region configured to linearly polarize light which is output from the light source and a second polarizing region configured to circularly polarize light which is output from the light source.

There is provided an optical system, including a light-transmitting substrate having at least two major surfaces parallel to each other edges, and an optical device for coupling light into the substrate by total internal reflection. The device includes a polarization sensitive reflecting surface.

A symmetric light guide optical element (“LOE”) and methods of fabrication thereof are disclosed. The method includes providing a plurality of transparent plates, each plate having two parallel surfaces, stacking a first subset of the plurality of plates on a transparent base block to form a first stack of plates, forming a sloped surface on one side of the first stack plates and the base block, stacking a second subset of the plurality of plates on the sloped surface to form a second stack of plates, and extracting a slice of the first stack, the base block, and the second stack, such that the slice includes at least a part of the base block interposed between plates of the first stack and plates of the second stack.

A light guide device includes an incident section, a parallel light guide body for light guide, and an emitting section. The emitting section includes a reflection unit formed by arraying a plurality of mirrors. The plurality of mirrors configuring the reflection unit are reflection elements having reflectance of P polarized light lower than reflectance of S polarized light. The plurality of mirrors configuring the reflection unit can be accompanied by wavelength plates to be adjacent to the mirrors.

A heterodyne two-dimensional grating measuring device and measuring method thereof includes a light source, a reading head, a photoelectric receiving module, and a signal processing system. The light source is configured to generate two beams of linearly polarized lights having characteristics of overlapping, polarization orthogonal, and fixed frequency difference. The reading head is configured to receive the two beams of the linearly polarized lights, the two beams of the linearly polarized lights are respectively incident on a surface of a moving two-dimensional measuring grating to generate ±1-order diffracted lights of two dimensions, and the ±1-order diffracted lights are respectively incident to the photoelectric receiving module through the reading head. The photoelectric receiving module is configured to generate beat frequency signals, the signal processing system is configured to perform differential calculation on the beat frequency signals to realize a displacement measurement of measuring grating for four-fold optical subdivision.

Embodiments of this application provide a display device module, including a display panel, a non-coaxial optical component, a first optical element, and a second optical element. The non-coaxial optical component includes an incident surface and an emergent surface, and the incident surface of the non-coaxial optical component faces the display panel, so that light emitted by the display panel is capable of being transmitted through the incident surface and transmitted from the emergent surface. In this application, a thickness of a display module in a head-mounted display device in a viewing direction of human eyes is reduced, and a compact design of the head-mounted display device is implemented.

The invention discloses a novel projector, comprising a sealed shell of electronic projector, an illumination system and a LED light source system, wherein the sealed shell is provided with an optical and internal circulation cooling assembly inside by area; the optical assembly comprises the projector working assembly. The invention is inside a sealed shell; the cold air far below normal temperature generated by semiconductor refrigeration piece takes away the heat on optical device, improving the heat dissipation efficiency. Simultaneously, because the cold air is inside a sealed shell, the optical device can be placed in a dust-free environment. The polarized light conversion prism converts the useless P light in conventional projector imagining into the useful S light, improving the light utilization, and increasing the brightness of projection at the same power. The LED light source is collimated by the collimating lens to meet PCS conversion requirement for polarized light converter.

A light source apparatus includes a red LD array that emits light in a red bandwidth, a blue LD array that emits light in a blue bandwidth, and a light combining part that includes a transmissive region and a reflecting region, the transmissive region transmitting the light emitted from the red LD array therethrough, the reflecting region reflecting the light emitted from the blue LD array.

An optical system includes: a beam splitter system configured to split an input beam into a plurality of output beams including a first output beam, a second output beam, and a third output beam; a first polarizing filter having a first polarization angle and configured to filter the first output beam to produce a first filtered output beam; a second polarizing filter having a second angle of polarization and configured to filter the second output beam to produce a second filtered output beam; and a third polarizing filter having a third angle of polarization and configured to filter the third output beam to produce a third filtered output beam, the first, second, and third angles of polarization being different from one another.