Provided is a design method for a diffractive optical element for being used for projecting an oblique line. The method comprises: determining an angle θ between an oblique line and a first direction (S101); according to the angle, determining a first cycle d1 of a diffractive optical element in the first direction and a second cycle d2 of the diffractive optical element in a second direction, wherein the first direction is perpendicular to the second direction, and the first cycle d1 and the second cycle d2 satisfy tgθ=d1/d2 (S102); and obtaining a phase distribution map of the diffractive optical element according to the first cycle d1, the second cycle d2 and a target pattern with an oblique line at 45° (S103). By means of the design method, the visual effect of an optical field projected by means of a diffractive optical element can be improved.

Provided is a design method for a diffractive optical element for being used for projecting an oblique line. The method comprises: determining an angle θ between an oblique line and a first direction (S101); according to the angle, determining a first cycle d1 of a diffractive optical element in the first direction and a second cycle d2 of the diffractive optical element in a second direction, wherein the first direction is perpendicular to the second direction, and the first cycle d1 and the second cycle d2 satisfy tgθ=d1/d2 (S102); and obtaining a phase distribution map of the diffractive optical element according to the first cycle d1, the second cycle d2 and a target pattern with an oblique line at 45° (S103). By means of the design method, the visual effect of an optical field projected by means of a diffractive optical element can be improved.

A machine readable symbol reader can provide illumination form portions other than or in addition to the head of the reader, to enhance the ability to successfully read machine-readable symbols, for example symbols on curved surfaces and/or DPM symbols. A machine readable symbol reader include a first set of receiving optics in a head of the reader and a second set of receiving optics in a portion of the reader other than the head, to provide an alternative line of sight or field of view.

A system for generating an extended specular lighting field for reading symbols on a reflective background surface is described. A scanner generates illumination for illuminating the symbols. Reflection of the illumination incident upon the reflective surface is retroreflected onto the symbols on the reflective surface. Reflection of the retroreflected light by the reflective surface is received by the scanner for processing information about the symbols. By using the reflective surface to help illuminate the symbols, an ordinary scanner can be used to read the symbols.

A machine readable symbol reader can provide illumination form portions other than or in addition to the head of the reader, to enhance the ability to successfully read machine-readable symbols, for example symbols on curved surfaces and/or DPM symbols. A machine readable symbol reader include a first set of receiving optics in a head of the reader and a second set of receiving optics in a portion of the reader other than the head, to provide an alternative line of sight or field of view.

An optical information detecting apparatus is formed as an integrated, solid state monolithic structure. The monolithic structure includes a plurality of light sensors disposed on a substrate and electrically isolated from one another, a plurality of light emitting elements disposed on the substrate and electrically isolated from one another, the light sensors being optically isolated from the light emitting elements, and a circuit connected to the light emitting elements to generate light towards a target and connected to the light sensors to detect reflected light from the target, wherein a signal is generated in response to the detected light. The signal is indicative of an optical characteristic of the target.

A scanner for scanning an item positioned in a scan volume can include: an electronically switchable mirror configured to switch between a reflective state and a transmissive state, a plurality of mirrors, and a camera having a sensor. In a method for scanning the item, the scanner can repeatedly: switch the switchable mirror from the reflective state to the transmissive state, image a first field of view of the item onto the sensor with light that reflects from at least one mirror and transmits through the switchable mirror, switch the switchable mirror from the transmissive state to the reflective state, and image a second field of view of the item onto the sensor with light that reflects from at least one mirror and reflects from the switchable mirror. In some examples, the scanner can synchronize the switching of the switchable mirror to a frame rate of the sensor.

An optical information detecting apparatus is formed as an integrated, solid state monolithic structure. The monolithic structure includes a plurality of light sensors disposed on a substrate and electrically isolated from one another, a plurality of light emitting elements disposed on the substrate and electrically isolated from one another, the light sensors being optically isolated from the light emitting elements, and a circuit connected to the light emitting elements to generate light towards a target and connected to the light sensors to detect reflected light from the target, wherein a signal is generated in response to the detected light. The signal is indicative of an optical characteristic of the target.

An optical information detecting apparatus is formed as an integrated, solid state monolithic structure. The monolithic structure includes a plurality of light sensors disposed on a substrate and electrically isolated from one another, a plurality of light emitting elements disposed on the substrate and electrically isolated from one another, the light sensors being optically isolated from the light emitting elements, and a circuit connected to the light emitting elements to generate light towards a target and connected to the light sensors to detect reflected light from the target, wherein a signal is generated in response to the detected light. The signal is indicative of an optical characteristic of the target.

An optical information detecting apparatus is formed as an integrated, solid state monolithic structure. The monolithic structure includes a plurality of light sensors disposed on a substrate and electrically isolated from one another, a plurality of light emitting elements disposed on the substrate and electrically isolated from one another, the light sensors being optically isolated from the light emitting elements, and a circuit connected to the light emitting elements to generate light towards a target and connected to the light sensors to detect reflected light from the target, wherein a signal is generated in response to the detected light. The signal is indicative of an optical characteristic of the target.