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| Number | Title | Issue Date |
| 7358472 | Low power phototransistor-based welding helmet providing reduced sensitivity to low intensity light and sharp phototransistor response to high intensity light An auto darkening eye protection device including a shutter assembly, a light sensing circuit, a control circuit and a power source. The shutter assembly is adjustable to a plurality of shade levels. The phototransistor of the light sensing circuit senses light from... | 04/15/2008 |
| 7161116 | Welding protective mask with illumination equipment A welding protective mask (1) includes illumination equipment (3) for illuminating a work area. The illumination equipment (3) includes an illumination device (5), a detection device (8) for detecting an ambient light intensity, an... | 01/09/2007 |
| 4863244 | Electro-optic welding lens assembly An electro-optic welding lens assembly for use in a welder's helmet or a protective eyeshield and including at least one liquid crystal filter element adapted to be controlled with regard to its light transmission as well as control means for changing the... | 09/05/1989 |
| 4620322 | Electro-optic welding lens assembly An electro-optic welding lens assembly for the use in a welder's helmet or protective eyeshield comprises a filter arrangement with at least one liquid crystal light shutter element and a control unit for changing the transmission rate of the filter assem... | 11/04/1986 |
| 4241286 | Welding helmet lens assembly A protective welding lens assembly for use as the eyepiece of a welding helmet in which the lens assembly can be changed from a light-transmitting condition to an essentially opaque condition of very small light transmission, and vice versa, in response t... | 12/23/1980 |
| 4237557 | Control system for welding helmet liquid crystal light shutter A control system and method for operating a welding helmet liquid crystal light shutter wherein opening of the liquid crystal light shutter is delayed by two or three seconds after a welding arc is extinguished to permit the welder to apply a welding elec... | 12/09/1980 |
| 4071912 | Light filter for welder's mask A welder's mask has a lens at least part of which is formed of an infrared filter, an ultaviolet filter, a polarizer, an analyzer, and an optoelectric element between the polarizer and analyzer. The optoelectric element may be a ceramic crystal or fluid c... | 02/07/1978 |
| 4039803 | Electro-optic welding helmet lens assembly A protective welding lens assembly for use as the eyepiece of a welding helmet. The lens assembly utilizes a liquid crystal light shutter together with an electrical circuit adapted to change the light shutter from a uniform light-transmitting condition t... | 08/02/1977 |
| 4039254 | Electro-optic welding lens assembly using multiple liquid crystal light shutters and polarizers A liquid crystal welding lens assembly for use as the eyepiece of a welding helmet in which the light transmission of the lens assembly is no greater than 0.01% during the existence of a welding arc. This is achieved with the use of at least two liquid cr... | 08/02/1977 |
