Abstract: A system for and a method of optical scanning which provide for focusing a light beam using one or more flex circuits, each flex circuit containing an aperture that is moved into or out of the outgoing optical path of a light beam via an electromagnetic mechanism. The electromagnetic mechanism includes a moving coil or moving magnet attached to each flex circuit for positioning the flex circuit aperture in or out of the outgoing optical path when the electromagnetic mechanism is actuated by an electric current. By positioning a greater or lesser number of apertures in the outgoing optical path, the final aperture size may be modified, thereby adjusting the focal location and depth of field of the light beam. Accordingly, the scanning system provides improved focusing characteristics, as well as an increased read range.

Abstract: An optical or symbol reader including CMOS circuitry preferably integrated on a single chip. A CMOS optical reader chip comprises a CMOS imaging array having a plurality of pixels each with a dedicated pixel-site circuit. Charge is accumulated at each pixel location transferred upon demand to a common bus. In a preferred embodiment, exposure time of the imaging array is controlled using a feedback loop. One or more exposure control pixels are positioned adjacent to or within the imaging array and receive light along with the imaging array. The charge of the exposure control pixel or pixels is measured against a threshold level, and the amount of time taken to reach the threshold level determines the time exposure of the pixels of the imaging array. CMOS signal processing circuitry is employed which, in combination with the exposure control circuitry, minimizes time-to-read over a large range of light levels, while performing spatially optimal filtering.

Abstract: An optical or symbol reader including CMOS circuitry preferably integrated on a single chip. A CMOS optical reader chip comprises a CMOS imaging array having a plurality of pixels each with a dedicated pixel-site circuit. Charge is accumulated at each pixel location transferred upon demand to a common bus. In a preferred embodiment, exposure time of the imaging array is controlled using a feedback loop. One or more exposure control pixels are positioned adjacent to or within the imaging array and receive light along with the imaging array. The charge of the exposure control pixel or pixels is measured against a threshold level, and the amount of time taken to reach the threshold level determines the time exposure of the pixels of the imaging array. CMOS signal processing circuitry is employed which, in combination with the exposure control circuitry, minimizes time-to-read over a large range of light levels, while performing spatially optimal filtering.

Abstract: An optical or symbol reader including CMOS circuitry preferably integrated on a single chip. A CMOS optical reader chip comprises a CMOS imaging array having a plurality of pixels each with a dedicated pixel-site circuit. Charge is accumulated at each pixel location transferred upon demand to a common bus. In a preferred embodiment, exposure time of the imaging array is controlled using a feedback loop. One or more exposure control pixels are positioned adjacent to or within the imaging array and receive light along with the imaging array. The charge of the exposure control pixel or pixels is measured against a threshold level, and the amount of time taken to reach the threshold level determines the time exposure of the pixels of the imaging array. CMOS signal processing circuitry is employed which, in combination with the exposure control circuitry, minimizes time-to-read over a large range of light levels, while performing spatially optimal filtering.

Abstract: An optical or symbol reader including CMOS circuitry preferably integrated on a single chip. A CMOS optical reader chip comprises a CMOS imaging array having a plurality of pixels each with a dedicated pixel-site circuit. Charge is accumulated at each pixel location transferred upon demand to a common bus. In a preferred embodiment, exposure time of the imaging array is controlled using a feedback loop. One or more exposure control pixels are positioned adjacent to or within the imaging array and receive light along with the imaging array. The charge of the exposure control pixel or pixels is measured against a threshold level, and the amount of time taken to reach the threshold level determines the time exposure of the pixels of the imaging array. CMOS signal processing circuitry is employed which, in combination with the exposure control circuitry, minimizes time-to-read over a large range of light levels, while performing spatially optimal filtering.

Abstract: An optical or symbol reader including CMOS circuitry preferably integrated on a single chip. A CMOS optical reader chip comprises a CMOS imaging array having a plurality of pixels each with a dedicated pixel-site circuit. Charge is accumulated at each pixel location transferred upon demand to a common bus. In a preferred embodiment, exposure time of the imaging array is controlled using a feedback loop. One or more exposure control pixels are positioned adjacent to or within the imaging array and receive light along with the imaging array. The charge of the exposure control pixel or pixels is measured against a threshold level, and the amount of time taken to reach the threshold level determines the time exposure of the pixels of the imaging array. CMOS signal processing circuitry is employed which, in combination with the exposure control circuitry, minimizes time-to-read over a large range of light levels, while performing spatially optimal filtering.

Abstract: An optical or symbol reader including CMOS circuitry preferably integrated on a single chip. A CMOS optical reader chip comprises a CMOS imaging array having a plurality of pixels each with a dedicated pixel-site circuit. Charge is accumulated at each pixel location transferred upon demand to a common bus. In a preferred embodiment, exposure time of the imaging array is controlled using a feedback loop. One or more exposure control pixels are positioned adjacent to or within the imaging array and receive light along with the imaging array. The charge of the exposure control pixel or pixels is measured against a threshold level, and the amount of time taken to reach the threshold level determines the time exposure of the pixels of the imaging array. CMOS signal processing circuitry is employed which, in combination with the exposure control circuitry, minimizes time-to-read over a large range of light levels, while performing spatially optimal filtering.

Abstract: A method and apparatus for improving the accuracy of bar and space measurements in a barcode scanner system utilizing second derivative signal processing is provided wherein edges are more accurately detected under low signal-to-noise conditions, such as when shot noise is the major source of noise in an input signal and the larger noise levels present during the light portions of the input signal may cause premature triggering of a light-to-dark transition in the output signal. In a preferred embodiment, an input capture circuit captures and stores the time of successive assertions of an STV signal corresponding to light-to-dark transitions. Upon detection by a second input capture circuit of a first assertion, following the STV assertions, of an RTV signal corresponding to dark-to-light transitions, the last STV signal time is stored and used with a previously stored RTV time to determine a space width. The new RTV signal time and the last STV signal time are then used to determine a bar width.

Abstract: A method and apparatus for reading bar codes or other images while reducing or eliminating the need for self-generated illumination. An image reader is preferably embodied as a handheld unit and comprises an efficient optical collection system including an aperture with a high aspect ratio and/or a multi-focal lens or lenses. An optically transmissive spacer affixed to the front of the handheld unit allows ambient light to be collected at close range, and a diffuser may be used to reflect ambient light from the handheld unit to provide additional illumination at close range. A masked CCD detector with rectangular pixels receives collected light and is coupled to an adaptive exposure circuit for preventing saturation of the CCD detector at high illumination levels. A correlated double sampling circuit coupled to the adaptive exposure circuit rejects common mode noise and allows operation in lower light levels.

Abstract: A method and apparatus for reading bar codes or other images while reducing or eliminating the need for self-generated illumination. An image reader is preferably embodied as a handheld unit and comprises an efficient optical collection system including an aperture with a high aspect ratio and/or a multi-focal lens or lenses. An optically transmissive spacer affixed to the front of the handheld unit allows ambient light to be collected at close range, and a diffuser may be used to reflect ambient light from the handheld unit to provide additional illumination at close range. A masked CCD detector with rectangular pixels receives collected light and is coupled to an adaptive exposure circuit for preventing saturation of the CCD detector at high illumination levels. A correlated double sampling circuit coupled to the adaptive exposure circuit rejects common mode noise and allows operation in lower light levels.

Abstract: A method and apparatus for improving the accuracy of bar and space measurements in a barcode scanner system utilizing second derivative signal processing is provided wherein edges are more accurately detected under low signal-to-noise conditions, such as when shot noise is the major source of noise in an input signal and the larger noise levels present during the light portions of the input signal may cause premature triggering of a light-to-dark transition in the output signal. In a preferred embodiment, an input capture circuit captures and stores the time of successive assertions of an STV signal corresponding to light-to-dark transitions. Upon detection by a second input capture circuit of a first assertion, following the STV assertions, of an RTV signal corresponding to dark-to-light transitions, the last STV signal time is stored and used with a previously stored RTV time to determine a space width. The new RTV signal time and the last STV signal time are then used to determine a bar width.

Abstract: A method and apparatus for reading bar codes or other images while reducing or eliminating the need for self-generated illumination. An image reader is preferably embodied as a handheld unit and comprises an efficient optical collection system including an aperture with a high aspect ratio and/or a multi-focal lens or lenses. An optically transmissive spacer affixed to the front of the handheld unit allows ambient light to be collected at close range, and a diffuser may be used to reflect ambient light from the handheld unit to provide additional illumination at close range. A masked CCD detector with rectangular pixels receives collected light and is coupled to an adaptive exposure circuit for preventing saturation of the CCD detector at high illumination levels. A correlated double sampling circuit coupled to the adaptive exposure circuit rejects common mode noise and allows operation in lower light levels.