Abstract: There is provided methods and apparatus for compensation of intensity profiles of imagers used in three-dimensional modelers. The intensity profile of the actinic radiation projected from the imager is determined by a variety of techniques, including but not limited to manually operated sensors, exposed and scanned actinic radiation-sensitive paper, and intensity profilers. Once the intensity profile of the imager is determined, each layer of the solidifiable liquid material is cured by projecting a plurality of patterns (as opposed to a single pattern) defining the two-dimensional cross-section of the part being cured. The patterns vary in duration, number, and/or shape to correlate to the intensity profile so that a single layer of selectively cured solidifiable liquid material is cured with a substantially equivalent (or otherwise controlled) amount of actinic radiation per unit of surface area to provide generally controlled and consistent part quality.

Abstract: There is provided methods and apparatus for improving the accuracy of three-dimensional objects formed by additive manufacturing. By depositing or hardening build material within the interior of the layers in certain patterns, the stresses that lead to curl in the object can be isolated and controlled. Similarly, certain patterns for depositing or hardening the build material provide for reduced layer thicknesses to improve the sidewall quality of the object being formed. The patterns within the interior of the layers can include gaps or voids for particular layers being deposited or hardened, and the gaps or voids can be partially filled, fully filled, or not filled at all when subsequent layers are deposited or hardened. Accordingly, the accuracy of three-dimensional objects formed by additive manufacturing is improved.

Abstract: There is provided methods and apparatus for compensation of intensity profiles of imagers used in three-dimensional modelers. The intensity profile of the actinic radiation projected from the imager is determined by a variety of techniques, including but not limited to manually operated sensors, exposed and scanned actinic radiation-sensitive paper, and intensity profilers. Once the intensity profile of the imager is determined, each layer of the solidifiable liquid material is cured by projecting a plurality of patterns (as opposed to a single pattern) defining the two-dimensional cross-section of the part being cured. The patterns vary in duration, number, and/or shape to correlate to the intensity profile so that a single layer of selectively cured solidifiable liquid material is cured with a substantially equivalent (or otherwise controlled) amount of actinic radiation per unit of surface area to provide generally controlled and consistent part quality.

Abstract: There is provided methods and apparatus for compensation of intensity profiles of imagers used in three-dimensional modelers. The intensity profile of the actinic radiation projected from the imager is determined by a variety of techniques, including but not limited to manually operated sensors, exposed and scanned actinic radiation-sensitive paper, and intensity profilers. Once the intensity profile of the imager is determined, each layer of the solidifiable liquid material is cured by projecting a plurality of patterns (as opposed to a single pattern) defining the two-dimensional cross-section of the part being cured. The patterns vary in duration, number, and/or shape to correlate to the intensity profile so that a single layer of selectively cured solidifiable liquid material is cured with a substantially equivalent (or otherwise controlled) amount of actinic radiation per unit of surface area to provide generally controlled and consistent part quality.

Abstract: There is provided methods and apparatus for compensation of intensity profiles of imagers used in three-dimensional modelers. The intensity profile of the actinic radiation projected from the imager is determined by a variety of techniques, including but not limited to manually operated sensors, exposed and scanned actinic radiation-sensitive paper, and intensity profilers. Once the intensity profile of the imager is determined, each layer of the solidifiable liquid material is cured by projecting a plurality of patterns (as opposed to a single pattern) defining the two-dimensional cross-section of the part being cured. The patterns vary in duration, number, and/or shape to correlate to the intensity profile so that a single layer of selectively cured solidifiable liquid material is cured with a substantially equivalent (or otherwise controlled) amount of actinic radiation per unit of surface area to provide generally controlled and consistent part quality.

Abstract: An optical navigation devices and methods that utilize an internal reflection surface to reflect and collimate sidelight from a light source are described. A light source is configured to emit light. The sidelight from the light source is reflected and collimated by an internal reflection surface towards a work surface. The light received by the sensor is used to measure movement of the optical navigation device relative to the work surface.

Abstract: An optical navigation devices and methods that utilize an internal reflection surface to reflect and collimate sidelight from a light source are described. A light source is configured to emit light. The sidelight from the light source is reflected and collimated by an internal reflection surface towards a work surface. The light received by the sensor is used to measure movement of the optical navigation device relative to the work surface.