Abstract: A light control film comprises a light input surface and a light output surface opposite the light input surface. Alternating transmissive regions and absorptive regions are disposed between the light input surface and the light output surface. The absorptive regions have an aspect ratio of at least 30 and the alternating transmissive region and absorptive regions have a relative transmission at a viewing angle of 0 degrees of at least 75%.

Abstract: A light control film is described comprising alternating transmissive regions and absorptive regions disposed between a light input surface and a light output surface. The absorptive regions have an aspect ratio of at least 30. In some embodiments, the alternating transmissive regions and absorptive regions have a transmission as measured with a spectrophotometer at a viewing angle of 0 degrees of at least 35, 40, 45, or 50% for a wavelength of the range 320-400 nm (UV) and/or at least 65, 70, 75, or 80% for a wavelength of the range 700-1400 nm (NIR). In another embodiment, the absorptive regions block light at the light input surface and light output surface and the maximum surface area that is blocked is less than 20% of the total alternating transmissive regions and absorptive regions. Also described are various optical communication systems comprising the light control films described herein and methods.

Abstract: A pressure sensing system includes a pressure transducer, a pressure manifold, and a heater assembly. The pressure transducer is configured to measure pressures at one or more locations of a vehicle engine. The pressure manifold is configured to cover a face of the pressure transducer and provide an interface for transferring air or gas generated at the one or more locations of the vehicle engine. The heater assembly is configured to heat one or more portions of the pressure transducer and one or more portions of the pressure manifold and maintain a temperature of each of the pressure transducer and the pressure manifold above a predetermined temperature level.

Abstract: A pressure sensing system includes a pressure transducer, a pressure manifold, and a heater assembly. The pressure transducer is configured to measure pressures at one or more locations of a vehicle engine. The pressure manifold is configured to cover a face of the pressure transducer and provide an interface for transferring air or gas generated at the one or more locations of the vehicle engine. The heater assembly is configured to heat one or more portions of the pressure transducer and one or more portions of the pressure manifold and maintain a temperature of each of the pressure transducer and the pressure manifold above a predetermined temperature level.

Abstract: A multi-function optical reader comprises an photosensor, such as a charge-device (CCD), and signal conditioning and processing circuitry including separate channels for handling data in different formats. A bar code processing channel digitizes the scan signal according to light and dark features using a first-derivative technique, and an OMR processing channel uses an adaptive threshold to adapt to different light conditions and provide a boundary line for digitizing light and dark features of the target scan line. A feature measurement circuit measures the widths of the light and dark regions as derived by the separate processing channels, and provides the feature measurements to a decoding system or host terminal processor. The scan rate of the optical reader can be adjusted according to the data format to be read or the level of ambient light, to avoid saturation. The optical reader can provide multiple depth-of-field zones, both internal and external to an optical reader housing.

Abstract: A multi-function optical reader comprises an photosensor, such as a charge-device (CCD), and signal conditioning and processing circuitry including separate channels for handling data in different formats. A bar code processing channel digitizes the scan signal according to light and dark features using a first-derivative technique, and an OMR processing channel uses an adaptive threshold to adapt to different light conditions and provide a boundary line for digitizing light and dark features of the target scan line. A feature measurement circuit measures the widths of the light and dark regions as derived by the separate processing channels, and provides the feature measurements to a decoding system or host terminal processor. The scan rate of the optical reader can be adjusted according to the data format to be read or the level of ambient light, to avoid saturation. The optical reader can provide multiple depth-of-field zones, both internal and external to an optical reader housing.

Abstract: A bar code scanner includes aseparate transmitter and receiver, each being able to ultrasonically transmit and receive data, respectively. The receiver transmits an acknowledgement signal when a protocol is received, and sends the acknowledgement signal to the transmitter which, unless it receives the acknowledgement signal, will retransmit the protocol a predetermined number of times. The transmitter includes a receiver which monitors an ultrasonic frequency band for a time period in which transmission by the transmitter is not allowed. The time period corresponds to a time when another ultrasonic signal in the ultrasonic frequency band is detected by the receiver of the transmitter. Transmission by the transmitter is allowed as soon as the another ultrasonic signal is no longer detected by the receiver of the transmitter.

Abstract: A digitizer for a barcode scanner includes an amplifier and a comparator. The amplifier receives a feedback signal and a differentiated return signal on a first port, and a reference voltage signal on a second port. Based on a difference between voltages on the first and second ports, the amplifier outputs an output signal, which is limited between a maximum voltage value and a minimum voltage value. The output signal is delayed in phase, and the phase-delayed signal is input to a first port of a comparator, while the undelayed output signal is input to a second port of the comparator. Based on a comparison of the voltages on the first and second ports of the comparator, the feedback signal having one of a first voltage value and a second voltage value is obtained.

Abstract: A light beam, which scans in opposite directions across a bar code, is controlled in velocity and scan angle by monitoring the voltage across a winding of a motor, such as one of the phase windings of a two phase stepper motor, which causes the beam to scan across a field of view where the bar code is located. In order to enable the winding, which carries current for driving the motor, circuitry that inhibits the voltage from inductive generation (the back EMF) into the winding during periods when the drive current is applied to the motor. The drive current is applied in pulses, and preferably in groups of pulses, which groups recur periodically. In one embodiment of the invention, which utilizes a motor with two phase windings, the groups of pulses are applied alternately to different ones of the windings and the voltage due to inductive generation is derived from one of these windings during the time period where the pulses are applied to the other winding.

Abstract: A bar code scanner includes a separate transmitter and receiver, each being able to ultrasonically transmit and receive data, respectively. The receiver transmits an acknowledgement signal when a protocol is received, and sends the acknowledgement signal to the transmitter which, unless it receives the acknowledgement signal, will retransmit the protocol a predetermined number of times. The transmitter includes a receiver which monitors an ultrasonic frequency band for a time period in which transmission by the transmitter is not allowed. The time period corresponds to a time when another ultrasonic signal in the ultrasonic frequency band is detected by the receiver of the transmitter. Transmission by the transmitter is allowed as soon as the another ultrasonic signal is no longer detected by the receiver of the transmitter.