603results about How to "Reduce the amount of light" patented technology

This invention provides an infrared illuminator and camera system for imaging of auto vehicle license plates. The system works in ambient light conditions, ranging from bright sunlight, to dim light, to dark, to zero ambient light. It yields high-contrast imaging of the letters and numbers on retro-reflective license plates. The images of the license letter and number combinations can be read manually by a remote operator. They can be converted to text format with optical character recognition computer hardware and software. The text data can then be compared to data files listing license numbers to provide further data about the owner of a licensed vehicle. A decision can be made quickly about whether to allow a vehicle to proceed through a gate, or whether to take other action. The system uses a mono camera that is enhanced for infrared sensitivity and combined with a high power infrared illuminator to maximize range at night, and with shutter speeds set up to capture clear license plate pictures even with fast moving vehicles and even with their headlights on and interfering with human observation of the license plates. Optical filtering to pass infrared in the range of the illuminator and to reduce light outside this range, combines with a lens set up, to avoid vertical smear and sensor overload caused by headlights at night and by highlight reflected glare from the sun in daytime.

A light-emitting device includes a substrate that is at least partially transparent to optical radiation and has a first index of refraction. A diode region is disposed on a first surface of the substrate and is configured to emit light responsive to a voltage applied thereto. An encapsulation layer is disposed on a second surface of the substrate and has a second index of refraction. An antireflective layer is disposed between a second surface of the substrate and the encapsulation layer. The antireflective layer has a graded index of refraction having values in a range between about the first index of refraction at a first surface of the antireflective layer and about the second index of refraction at a second surface of the antireflective layer. The encapsulation layer may also be omitted and the antireflective layer may separate the substrate, which has a first index of refraction, from air, which has a second index of refraction. Non “flip-chip” embodiments are also disclosed.

A stitching type exposure apparatus for successively exposing an image of a pattern of a reticle (Ri) on different areas of a surface of a substrate (4) while overlaying parts of the same, wherein a density filter (Fj) having a light attenuating part for reducing the amount of light of overlaid parts of the image of the pattern in a sloping manner is provided in the vicinity of the reticle (Ri), the density filter (Fj) is held at a filter stage (FS) for adjusting the posture, the posture of the density filter (Fj) is detected by an illumination uniformity sensor (126) on the substrate stage (6), and the posture of the density filter (Fj) is matched with the posture of the reticle (Ri) by the filter stage (FS).

Solar cells in accordance with the present invention have reduced ohmic losses. These cells include photo-receptive regions that are doped less densely than adjacent selective emitter regions. The photo-receptive regions contain multiple four-sided pyramids that decrease the amount of light lost to the solar cell by reflection. The smaller doping density in the photo-receptive regions results in less blue light that is lost by electron-hole recombination. The higher doping density in the selective emitter region allows for better contacts with the metallic grid coupled to the multiple emitter regions. Preferably, the selective emitter and photo-receptive regions are both implanted using a narrow ion beam containing the dopants.

A photoelectric conversion device including a plurality of pin junction layers, wherein at least a p-layer adjacent to an n-layer is formed of a stack of an amorphous silicon layer as a first p-layer and an amorphous silicon layer as a second p-layer, the first p-layer having a thickness of 5 nm or less and containing a p-type impurity and an n-type impurity, and the second p-layer having a p-type impurity concentration gradually decreasing as it is closer to an i-layer.