An optical communication device can address these and other issues by utilizing a system and method in which an optical device emits a series of laser pulses that trace a spiral path over a coverage area. Each laser pulse containing a packet of information modulated at a relatively rate to help mitigate adverse effects from device movements, scintillation, and the like. The beam width of the laser, speed of the scan (along the spiral path), and number of laser pulses can be configured such that corresponding response pulses (e.g., retro-modulated pulses) received from an illuminated tag within the coverage may have a variety of different amplitudes, increasing the likelihood that at least one of the response pulses will have power characteristics that facilitate a proper decoding of the response pulse.

A digital imaging based symbol reading system has the capacity to automatically read both visible and invisible symbols in the same application environment. Typically, the system reads the symbols in a user-transparent manner. The system may employ visible/invisible illumination switching during operation. The system may include LED illumination sources. A method for reading both visible and invisible symbols using a single device is also disclosed.

A method for glare reduction may be implemented by a graphical code reader. The graphical code reader includes an optic system, a plurality of light sources, and a control system. The control system is configured to determine that glare is present in an image captured by the optic system by identifying reflection from at least one of the plurality of light sources. The control system may take a corrective action to reduce the glare in subsequent images. The control system may be configured to take a first corrective action if a diffraction pattern is present at a periphery of the glare, and take a second corrective action if a diffraction pattern is not present at the periphery of the glare.

A method and apparatus for generating 3D-maps for acquiring three-dimensional (3D) maps are presented. The method includes analyzing at least one image acquired by a passive sensor to identify a plurality of objects in the at least one image; classifying the plurality of objects; determining, based on the classification, whether to passively measure a distance to each of the plurality of objects; passively measuring the distance to at least one of the plurality of objects based on the determination; actively measuring a distance to some of the plurality of objects, wherein the distance to one of the same of the plurality of objects is actively measured when the distance to the object cannot be passively measured; and generating a 3D map of a scene based on the distance measured to each of the plurality of objects.

A method for glare reduction may be implemented by a graphical code reader. The graphical code reader includes an optic system, a plurality of light sources, and a control system. The control system is configured to determine that glare is present in an image captured by the optic system by identifying reflection from at least one of the plurality of light sources. The control system may take a corrective action to reduce the glare in subsequent images. The control system may be configured to take a first corrective action if a diffraction pattern is present at a periphery of the glare, and take a second corrective action if a diffraction pattern is not present at the periphery of the glare.

An optical communication device can address these and other issues by utilizing a system and method in which an optical device emits a series of laser pulses that trace a spiral path over a coverage area. Each laser pulse containing a packet of information modulated at a relatively rate to help mitigate adverse effects from device movements, scintillation, and the like. The beam width of the laser, speed of the scan (along the spiral path), and number of laser pulses can be configured such that corresponding response pulses (e.g., retro-modulated pulses) received from an illuminated tag within the coverage may have a variety of different amplitudes, increasing the likelihood that at least one of the response pulses will have power characteristics that facilitate a proper decoding of the response pulse.

An information recording medium according to one embodiment includes a substrate, a first image, and a second image. The first image is provided on the substrate, emits light when irradiated with first excitation light having a first wavelength, and includes phase-modulated first information. The second image is provided on the substrate, emits light when irradiated with second excitation light having a second wavelength different from the first wavelength, and includes phase-modulated second information.

A method for glare reduction may be implemented by a graphical code reader. The graphical code reader includes an optic system, a plurality of light sources, and a control system. The control system is configured to determine that glare is present in an image captured by the optic system by identifying reflection from at least one of the plurality of light sources. The control system may take a corrective action to reduce the glare in subsequent images. The control system may be configured to take a first corrective action if a diffraction pattern is present at a periphery of the glare, and take a second corrective action if a diffraction pattern is not present at the periphery of the glare.

Systems and methods provide an illumination assembly for a mark reader. A light transmitter is arranged in a surrounding relationship to an interior area, with the light transmitter having a proximal end and a distal end. An illumination source provides a light for transmission into the light transmitter. The light transmitter distal end allows the light from within the light transmitter to pass through and out of the distal end to provide bright field illumination and dark field illumination. The light transmitter distal end may include a first portion and a second portion, where light from within the light transmitter passes through and out of the first portion to provide bright field illumination, and light from within the light transmitter passes through and out of the second portion to provide dark field illumination.

A method for glare reduction may be implemented by a graphical code reader. The graphical code reader includes an optic system, a plurality of light sources, and a control system. The control system is configured to determine that glare is present in an image captured by the optic system by identifying reflection from at least one of the plurality of light sources. The control system may take a corrective action to reduce the glare in subsequent images. The control system may be configured to take a first corrective action if a diffraction pattern is present at a periphery of the glare, and take a second corrective action if a diffraction pattern is not present at the periphery of the glare.