Abstract: An optical test structure includes a substrate and at least one optical unit. The at least one optical unit is disposed on the substrate, and includes a first optical element, a second optical element, a third optical element, and a fourth optical element which are spaced apart from each other. The second optical element is disposed between the first optical element and the third optical element. The third optical element is disposed between the second optical element and the fourth optical element. A size of the third optical element is larger than a size of each of the first optical element, the second optical element, and the fourth optical element. The size of each of the second optical element and the fourth optical element is larger than the size of the first optical element.

Abstract: Various embodiments of the present disclosure are directed towards a camera module comprising flat lenses. Flat lenses have reduced thicknesses compared to other types of lenses, whereby the camera module may have a small size and camera bumps may be omitted or reduced in size on cell phones and the like incorporating the camera module. The flat lenses are configured to focus visible light into a beam of white light, split the beam into sub-beams of red, green, and blue light, and guide the sub-beams respectively to separate image sensors for red, green, and blue light. The image sensors generate images for corresponding colors and the images are combined into a full-color image. Optically splitting the beam into the sub-beams and using separate image sensors for the sub-beams allows color filters to be omitted and smaller pixel sensors. This, in turn, allows higher quality imaging.

Abstract: A photoconductive layer with electrical property adjustable via control of intensity or location of illumination by a light source is provided. The photoconductive layer has at least one charge generation material and at least one binder for distributing the charge generation material within the body of the layer. The localized change of electrical property in the photoconductive layer arises on and beneath the surface area of the layer illuminated by the light source via actuated bulk change in electrical charge contributed by the charge generation material in the area.