Abstract: A photocurrent sensing circuit having a stabilized feedback loop comprises a photocurrent generator including a photodiode generating the photocurrent in proportion to an amount of incident light and applying the photocurrent to an output node, a switching unit applying the photocurrent applied to a control node to a voltage-generating capacitor when a shutter signal is in a first state, and applying a predetermined current to the control node when the shutter signal is in a second state, and a circuit stabilizer applying the photocurrent applied to the output node to the control node, and always forming a feedback loop of the photodiode through the photocurrent applied to the output node, wherein the circuit stabilizer comprises a first NMOS transistor forming the feedback loop of the photodiode in response to the photocurrent input to the output node when the predetermined current is applied to the control node, breaking the feedback loop and applying the photocurrent applied to the output node to the contr

Abstract: A method and apparatus for protecting a photodiode of an optical receiver from overload optical signals by monitoring an operating parameter of the photodiode, determining if the operating parameter indicates that the photodiode is in a potential overload state in which the photodiode is susceptible to an overload optical signal; and applying a predetermined safe gain setting to the photodiode if a potential overload state is detected. The potential overload state may be a loss of signal condition, or detection of an overload optical power incident the photodiode.

Abstract: The invention provides a method of using at least one sensor sensitive to infrared radiation for inspecting hollow, transparent or translucent articles at high temperature leaving various different forming cavities. The method includes a step of evaluating the level of infrared radiation from the articles coming from the forming cavities so as to adapt the exposure of the sensor in a subsequent step of inspecting the articles in such a manner as to cause the response of the sensor to be uniform regardless of the different cavities from which the articles come.

Abstract: An object surface characterization system with adaptive lighting control includes a light projector, a light source, a camera, a processor and a memory subsystem. The processor is coupled to the light projector, the light source and the camera, as well as the memory subsystem. The memory subsystem stores code that, when executed by the processor, instructs the processor to perform a number of steps to achieve adaptive lighting control for the system.

Abstract: An avalanche photodiode with a wide dynamic range. An avalanche photodiode with a wide dynamic range is used in fiber-optic communication applications where optical signals of varying powers may be received. The avalanche photodiode includes a field control layer. A doping thickness product can be configured to determine a dynamic range of the avalanche photodiode. The gain of the avalanche photodiode is controllable by adjusting a bias voltage across the avalanche photodiode.

Abstract: A range discriminating optical sensor for use in a vehicle safety system is provided. The range discriminating sensor is designed to create a small depth of field such that objects at a range outside of the depth of field are eliminated from the image. Generally, the optical sensor uses a large aperture to limit the depth of field. An electronic imaging element is used to detect the image projected by the lens. The electronic imaging element may have a small pixel size which further reduces the depth of field. A signal processor can be used to determine the distance from the image sensor with objects with the selected depth of field appearing in focus and those outside of the depth of field appearing out of focus.

Abstract: An optical position-tracking system comprises an optical device for generating an incident light beam and a reference light beam from a light beam. Moreover, the optical position-tracking system further comprises a light beam steering device for sweeping the incident light beam through an angular range to cause a reflection of the incident light beam by a target, whereas the reflection of the incident light beam is directed to interfere with the reference light beam to form an interference light beam. Additionally, the optical position-tracking system enables determination of a position of the target using an interferometric technique utilizing an angular value of the incident light beam and the interference light beam, whereas the angular value depends on the reflection.

Abstract: An imaging system (10) has a fixed lens combination (22), a spatial light modulator (SLM) (20) and a linear detector array (12). A scene image is scanned across a simple array (12) in a direction perpendicular to the array (12) by the SLM (20). This is achieved by displaying a diffraction pattern on the SLM that changes to achieve the scanning. The diffraction pattern displayed typically has a linear element (40) and a quadratic element (42). By having a programmably changed combined chirp pattern (36) displayed on the SLM, and by being able to change it thousands of times a second, an army with fast read out can take the place of a 2-D imaging array.

Abstract: It is an object of the present invention to adjust the focus position of an optical pickup. A brightness measuring apparatus having a half mirror and an objective lens focusing on the half mirror is disposed at a position facing an optical pickup PUi, in a manner such that the objective lens OB of the optical pickup PUi faces the half mirror. Then, the optical pickup PUi is operated to start a focus servo, while the position of multi-lens provided in the optical pickup PUi is changed continuously, thereby measuring a highest brightness of a spot light image incident on the half mirror through the objective lens, by virtue of the brightness measuring apparatus. Subsequently, a highest brightness change caused by changing the position of the multi-lens ML is inspected so as to fix the multi-lens ML at a position when the maximum highest brightness has been obtained, thereby effecting an optimum focus position adjustment for an optical pickup.

Abstract: An object is held on a stage of an equipment, the stage is rotated in order to acquire a detection signal corresponding to a position of an outer peripheral edge of the object, a displacement of the object with respect to an alignment reference position is obtained based on this detection signal, and the stage is subjected to movement control so as to eliminate this displacement, thereby aligning the object.

Abstract: A method and corresponding device for determining the phase and/or amplitude data of an electromagnetic wave. The method comprises the steps: beaming an electromagnetic wave onto the surface of at least one pixel having at least two light sensitive modulation gates Gam, Gbm and associated accumulation gates Ga and Gb, applying modulation voltages Uam(t) and Ubm(t) to gates Gam and Gbm, applying a direct voltage to accumulation gates Ga and Gb, wherein the charge carriers produced in modulation gates Gam and Gbm by the incident electromagnetic wave being subjected to a potential gradient due to the modulation voltages Uam(t) and Ubm(t), thereby drifting to the corresponding accumulation gate Ga or Gb, and forwarding the charge carriers to evaluation electronics. A plurality of corresponding pixels can be assembled to form an array.

Abstract: Speckle based optical navigation is improved by increasing the collection efficiency of the photodetector through the introduction of a lightpipe or reflector technology. For example, the use of elliptical sidewalls and diffraction gratings in conjunction with a lightpipe leads to improvements in collection efficiency.

Abstract: A method and apparatus is used to detect and compensate for printhead rotation in an inkjet printer. The detecting operation includes receiving an initial image of a pattern taken from a medium as the printhead passes over the medium, receiving a subsequent image of the pattern taken from the medium as the printhead continues to pass over the medium, comparing the initial image of the pattern and the subsequent image of the pattern taken from the medium and identifying a rotation of the printhead in the inkjet printer passing over the medium if the comparison indicates the initial image of the pattern is rotated relative to the subsequent image of the pattern. The compensation operation includes modifying the timing settings associated with the firing of the nozzles in the inkjet printhead to compensate for the rotation of the printhead.

Abstract: A light sensor and method of detecting light using the light sensor are provided. The light sensor includes a container having an anode compartment and a cathode compartment. The anode compartment has an anode and the cathode compartment has a cathode. The container also includes a transparent portion that allows light into the anode compartment. A membrane separates the anode compartment and the cathode compartment. The membrane is able to allow protons to pass from the anode compartment to the cathode compartment. The anode compartment includes a photon-converting compound (“PCC”) for generating electrons by reaction with light. Also included are an imaging device and a method of using the imaging device.

Abstract: An optical interconnect system having a GRIN rod lens, the GRIN rod lens having a first end and a second end, and further having a preselected length, a preselected width and a preselected index of refraction. Means are fixedly secured to the first end of the GRIN rod lens for emitting electromagnetic radiation and means are fixedly secured to said second end of said GRIN rod lens for receiving the emitted electromagnetic radiation. The GRIN rod lens forms an image of the emitting means onto the receiving means and overcomes problems associated with misalignment. Further embodiments of this optical interconnect system are capable of use in even further applications in an environment where alignment problems are at issue.

Abstract: The present invention provides for measuring a particle size distribution of a population of particles using a light scattering particle sizing instrument having a plurality of selectable imaginary component values of the refractive index. The particles each having a particle size and the process includes the steps of: (i) providing a population of the particles, wherein the particles have a refractive index; (ii) determining a real component of the refractive index of the particles using the Becke Line Method; (iii) determining an imaginary component of the refractive index of the particles; and (iv) determining the particle size distribution of the particles by the light scattering particle sizing instrument wherein the particle size distribution is determined using the real component of the refractive index measured in step (ii) and the imaginary component of the refractive index determined in step (iii).

Abstract: The present invention related to a water detector for use in determining the presence of sufficient water in irrigation systems and plant cultures in general. The detector includes a probe and the presence of water in a soil induces modifications in the optical properties of the probe. The optical properties are monitored and used to control the activation or deactivation of the irrigation system, emit a warning signal or provide a reference value of water potential for monitoring purposes.

Abstract: The invention relates to the improvement in the quality of cathodes produced in an electrolysis process. The surface of a cathode lifted from the cell during the cathode cycle is photographed and the physical quality of the cathode can be investigated in real time by means of equipment based on image-analysis. On the basis of the quality of the cathode surface, it is possible to monitor and control the electrolysis conditions in order to improve the quality of the cathode. The method is extremely suitable for the electrolytic purification of copper.

Abstract: A signal processing apparatus includes a lens, an image sensing device placed on an imaging plane of the lens, and a limb darkening correction section which corrects limb darkening only in the horizontal direction of the image sensing device with respect to a video signal of an object sensed by the image sensing device.