Abstract: Briefly, in accordance with one or more embodiments, an input device may be utilized in conjunction with a scanned beam display or the like, or may be based on the scanning platform as used in a scanned beam display such as a MEMS based scanner. An input event such as illumination of a photodetector or reflection of a scanned beam off of a retroreflector may be correlated with a timing event of the scanning platform such as a refresh signal, or a horizontal and vertical sync signals. The correlation of the timing event may be representative of an X-Y location, and in some embodiments of a Z location, that may be utilized to provide input data back to a host device.

Abstract: A drive circuit includes a generator and a driver. The generator generates a signal having a period and a varying amplitude during a driving portion of the period, and the driver is coupled to the generator and drives a plate of an electrostatically drivable plant with the signal. The drive circuit may be used to drive a mirror plate of a comb-drive MEMS mirror.

Abstract: A encoded image projection system (100) is configured to determine the proximity of the system to a projection surface (106). The encoded image projection system (100) includes a light encoder (105) that scans a non-visible light beam (115) on the projection surface (106) selectively when scanning visible light to create an image. A detector (118) is then configured to receive reflections of the non-visible light beam (115) from the projection surface (106). A control circuit (120) is configured to determine the distance (124) between the projection surface (106) and the system from, for example, intensity data or location data received from the detector (118). Where the distances (124) are below a threshold, the control circuit (120) can either reduce the output power of the system or turn the system off.

Abstract: Embodiments relate to a MEMS device including a scanner rotatable about at least one rotation axis, with the scanner having a characteristic resonant frequency. According to one embodiment, the MEMS device includes drive electronics operable to generate a drive signal that causes the scanner to oscillate at an operational frequency about the at least one rotation axis. The drive signal has a drive frequency selected to be about equal to the characteristic resonant frequency or a sub-harmonic frequency of the characteristic resonant frequency. According to another embodiment, the drive electronics are operable to generate a drive signal having a plurality of drive-signal pulses that moves the scanner at an operational frequency and sensing electronics are operable to sense a position of the scanner only when the drive-signal pulses of the drive signal are not being transmitted by the drive electronics. The MEMS device embodiments may be incorporated in scanned beam imagers, endoscopes, and displays.

Abstract: Briefly, in accordance with one or more embodiments, an operational state of a MEMS device of a scanner system may be determined. In the event it is determined that the MEMS device is possibly operating in an unsafe mode, the laser may be turned off and/or the MEMS device may be shut down. An operational state of the MEMS device may be determined for example by obtaining a MEMS drive voltage sense signal and/or a MEMS drive current sense signal, and a potentially unsafe mode of operation may be identified if one or more of such signals are not at proper values with respect to predetermined threshold values.

Abstract: Briefly, in accordance with one or more embodiments, a scanner system may scan a target based on a first derivative of a reflectance profile received from a scanned target. Positive and negative threshold values may comprise a static portion and a dynamic portion. The static portion may comprise a constant value, and the dynamic portion may be based at lest in part on a charge profile, or a discharge profile, of a capacitor. The threshold for generating the digital signal may be set lower when the amplitude of the first derivative is lower, and higher when the amplitude of the first derivative is higher.

Abstract: A photo-detector circuit for barcode scanners, endoscopes, and the like, includes a large area PIN photo-diode and an amplifier. Adverse effects associated with a terminal capacitance from the large area PIN diode may be minimized by maintaining a relatively constant voltage across the input terminals of the amplifier. Noise levels may be minimized by the arrangement of the amplifier circuit and the large area PIN diode resulting in an increased signal-to-noise ratio and an increased gain-bandwidth product. Due to the large numerical aperture of the photo-detector, increased resolution and/or lower output power in a reflective imaging system may be obtained with relatively low cost components. Detection area of the large area PIN diode may be larger than approximately 25 mm2 when compared to typical PIN diodes used in photo-detector applications.

Abstract: Briefly, in accordance with one or more embodiments, a MEMS device for a scanner system may be driven in a non-resonant mode of operation. The drive signal provided to the MEMS device may be tailored to prevent the MEMS device from exhibiting resonance characteristics and to cause the MEMS device to operate non-resonantly. In one or more embodiments, a filter may be used to tailor the frequency components of the drive signal, for example to sufficiently attenuate frequency components at or near the resonant frequency of the drive signal. A direct current signal may be provided to the MEMS device to provide an offset to scanned light beam for example to provide beam steering, and the sweep range and/or sweep frequency may be adjusted for example to steer the scanning field of view off axis from the user pointing axis.

Abstract: A encoded image projection system (100) is configured to determine the proximity of the system to a projection surface (106). The encoded image projection system (100) includes a light encoder (105) that scans a non-visible light beam (115) on the projection surface (106) selectively when scanning visible light to create an image. A detector (118) is then configured to receive reflections of the non-visible light beam (115) from the projection surface (106). A control circuit (120) is configured to determine the distance (124) between the projection surface (106) and the system from, for example, intensity data or location data received from the detector (118). Where the distances (124) are below a threshold, the control circuit (120) can either reduce the output power of the system or turn the system off.

Abstract: Briefly, in accordance with one or more embodiments, an operational state of a MEMS device of a scanner system may be determined. In the event it is determined that the MEMS device is possibly operating in an unsafe mode, the laser may be turned off and/or the MEMS device may be shut down. An operational state of the MEMS device may be determined for example by obtaining a MEMS drive voltage sense signal and/or a MEMS drive current sense signal, and a potentially unsafe mode of operation may be identified if one or more of such signals are not at proper values with respect to predetermined threshold values.

Abstract: Briefly, in accordance with one or more embodiments, an input device may be utilized in conjunction with a scanned beam display or the like, or may be based on the scanning platform as used in a scanned beam display such as a MEMS based scanner. An input event such as illumination of a photodetector or reflection of a scanned beam off of a retroreflector may be correlated with a timing event of the scanning platform such as a refresh signal, or a horizontal and vertical sync signals. The correlation of the timing event may be representative of an X-Y location, and in some embodiments of a Z location, that may be utilized to provide input data back to a host device.

Abstract: Briefly, in accordance with one or more embodiments, an operational state of a MEMS device of a scanner system may be determined. In the event it is determined that the MEMS device is possibly operating in an unsafe mode, the laser may be turned off and/or the MEMS device may be shut down. An operational state of the MEMS device may be determined for example by obtaining a MEMS drive voltage sense signal and/or a MEMS drive current sense signal, and a potentially unsafe mode of operation may be identified if one or more of such signals are not at proper values with respect to predetermined threshold values.

Abstract: Embodiments relate to a MEMS device including a scanner rotatable about at least one rotation axis, with the scanner having a characteristic resonant frequency. According to one embodiment, the MEMS device includes drive electronics operable to generate a drive signal that causes the scanner to oscillate at an operational frequency about the at least one rotation axis. The drive signal has a drive frequency selected to be about equal to the characteristic resonant frequency or a sub-harmonic frequency of the characteristic resonant frequency. According to another embodiment, the drive electronics are operable to generate a drive signal having a plurality of drive-signal pulses that moves the scanner at an operational frequency and sensing electronics are operable to sense a position of the scanner only when the drive-signal pulses of the drive signal are not being transmitted by the drive electronics. The MEMS device embodiments may be incorporated in scanned beam imagers, endoscopes, and displays.

Abstract: Briefly, in accordance with one or more embodiments, a proximity detector is placed proximate to projector to detect an obstruction disposed proximate to the projector. The proximity detector is capable of estimating the distance from an object to the projector. If an object is detected within a minimum distance, the projector operation may be altered, for example to cause the projector to turn off, or to reduce the intensity of emitted light so that the power of the emitted light the minimum distance will be reduced to below a selected range. Furthermore, if an object cannot be detected within or near a maximum distance, the projector operation may likewise be altered, for example the proximity detector may cause the projector to turn off.

Abstract: A portable end device, such as a bar code scanner, may be equipped with auxiliary interfaces. The auxiliary interfaces may be easily added to the end device as a replaceable cover, such as a replaceable battery door. A signal path conducts signals to and from the replaceable cover. One auxiliary interface is a Bluetooth radio. Data integrity protocols may be selected to guarantee delivery and guarantee no duplicate deliveries. Host pairing algorithms may provide standard or strong pairing with a host computer. Ergonomic interface features allow a user to control and monitor the operation of the end device and the data link with minimal hardware cost and battery life impact. Host software programs provide data routing, automatic reestablishment of the data link, and other functions. The system is adaptable to a wide array of use environments through the selection of timer parameters in the end device.

Abstract: Briefly, in accordance with one or more embodiments, an operational state of a MEMS device of a scanner system may be determined. In the event it is determined that the MEMS device is possibly operating in an unsafe mode, the laser may be turned off and/or the MEMS device may be shut down. An operational state of the MEMS device may be determined for example by obtaining a MEMS drive voltage sense signal and/or a MEMS drive current sense signal, and a potentially unsafe mode of operation may be identified if one or more of such signals are not at proper values with respect to predetermined threshold values.

Abstract: Briefly, in accordance with one or more embodiments, a MEMS device for a scanner system may be driven in a non-resonant mode of operation. The drive signal provided to the MEMS device may be tailored to prevent the MEMS device from exhibiting resonance characteristics and to cause the MEMS device to operate non-resonantly. In one or more embodiments, a filter may be used to tailor the frequency components of the drive signal, for example to sufficiently attenuate frequency components at or near the resonant frequency of the drive signal. A direct current signal may be provided to the MEMS device to provide an offset to scanned light beam for example to provide beam steering, and the sweep range and/or sweep frequency may be adjusted for example to steer the scanning field of view off axis from the user pointing axis.

Abstract: Briefly, in accordance with one or more embodiments, a scanner system may scan a target based on a first derivative of a reflectance profile received from a scanned target. Positive and negative threshold values may comprise a static portion and a dynamic portion. The static portion may comprise a constant value, and the dynamic portion may be based at lest in part on a charge profile, or a discharge profile, of a capacitor. The threshold for generating the digital signal may be set lower when the amplitude of the first derivative is lower, and higher when the amplitude of the first derivative is higher.

Abstract: Aspects of the subject matter described herein relate to reducing error in images obtained from an image-acquiring system. An image-acquiring system may be modeled as light received from a primary path, light received from a secondary path, and light received from all other paths. Light received from the secondary and other paths may cause error in images captured by the image-acquiring system. By compensating for this light, the error may be reduced. Other aspects are described in the specification.

Abstract: A drive circuit includes a generator and a driver. The generator generates a signal having a period and a varying amplitude during a driving portion of the period, and the driver is coupled to the generator and drives a plate of an electrostatically drivable plant with the signal. The drive circuit may be used to drive a mirror plate of a comb-drive MEMS mirror.