Microsoft Technology Licensing, LLC

Algird Michael Gudaitis

Mark Alan Champion

Raymond Kirk Price

Michael Anthony Hall

John Allen Tardif

Wenjun Liao

Gregory Theodore Gibson

Niranjan Achugundla Puttaswamy

Sheethal Somesh Nayak

Cyrus Soli Bamji

Dawson Yee

Barry Thompson

Zhanping Xu

Matthew D Morris

Travis Perry

Stefan Jon Kristjansson

Sunil Prakash Acharya

Andrew Dean Payne

Brock McCray Roland

Mike Fenton

Laurentiu Olariu

Larry Prather

Michael Hall

This disclosure provides methods and systems that adaptively adjust the gain of the drive signal to a slow-scan mirror to compensate and stabilize the mirror to achieve desired performance metrics. Non-ideal characteristics of the slow-scan mirror, including the mirror and related assembly, exhibit behaviors that impact the overall gain of the device, which changes over time and operating environment. To compensate for these non-ideal characteristics, the drive signal to the slow-scan mirror may need to be adjusted to achieve the desired beam deflection angle. An adaptive inner loop gain control structure may be employed to dynamically adjust the gain of the inner-control loop to achieve a target gain such that the overall gain variations from the slow scan mirror and other components are scan mirror such that compensated and stabilized. The parameters, logic and blocks of the inner loop gain control may be implemented in hardware, software, or combinations thereof.

Adaptive inner loop gain control for laser beam scanning displays

Controlling a mirror in a MEMS based projector. A method includes iteratively performing various acts. The method includes inputting a time domain target wave array, with target elements, to a system for a MEMS coupled to the mirror of the projector. The time domain target wave array includes a set of n target elements. The method further includes driving the driver to move the mirror using elements in a drive array comprising a set of drive elements. The method further includes sampling a time domain output wave for the movement of the mirror to construct an output wave array with output elements corresponding to the target elements. The method further includes identifying errors between the target elements and the output elements. The method further includes modifying the drive elements in the drive array to attempt to minimize the errors when driving the MEMS on subsequent drive cycles.

MEMS control method to provide trajectory control

Examples are disclosed herein related to controlling a scanning mirror system. One example provides a display device, comprising a light source, a scanning mirror system configured to scan light from the light source in a first direction at a first, higher scan rate, and in a second direction at a second, lower scan rate, and a drive circuit configured to control the scanning mirror system to display video image data by providing a control signal to the scanning mirror system to control scanning in the second direction, and for each video image data frame of at least a subset of video image data frames, combining the control signal with an adjustment signal to adjust the scanning in the second direction, the adjustment signal comprising a low pass filtered signal with a cutoff frequency based on a lowest resonant frequency of the scanning mirror system in the second direction.

Synchronizing scanning display with video

The techniques disclosed herein provide apparatus, methods and systems that adaptively adjust the signal waveform (or waveshape) of the drive signal to a slow-scan mirror to compensate for non-linearities observed in the slow-scan feedback signal from a slow-scan mirror. Over large scan angles and high temperatures, the slow-scan mirror in a laser beam scanning device may exhibit a nonlinear response to the drive signal that results in poor image quality issues such as bright lines, bands in the display image, and image distortion. The presently disclosed technologies track the linearity performance of the overall system by detecting non-linearities in waveform of the slow-scan feedback signal real time, and consequently apply a pre-distortion to the drive waveform to compensate for these detected non-linearities. The parameters, logic and blocks of the control may be implemented in hardware, software or combinations thereof.

Adaptive waveform non-linearity compensation for laser beam scanning displays

The description relates to laser control. One example can include a laser that has a laser emitter configured to generate a laser beam for intervals of time (e.g., pixel times). The laser can have a compensation and control component configured to receive a predicted laser emitter temperature of the laser emitter, obtain a desired optical power for an interval, and compute a compensated electrical current for the interval utilizing multiple light to current look up tables. Individual light to current look up tables can relate to specific laser emitter temperatures.

Laser control

The present disclosure relates to apparatuses and methods of providing an ideal diode function to a battery having a protective field effect transistor (FET). An apparatus may include the protective FET configured to selectively connect an external voltage to a battery for charging the battery. The apparatus may also include a controller coupled with a gate of the protective FET via a node and configured to enable the protective FET. The apparatus may further include an override circuit coupled to the node and configured to selectively draw current away from the gate of the protective FET based on the external voltage or to interrupt the path from a controller to a protective FET. The override circuit of the apparatus may provide protection from cross-charging of the battery by a second battery while using the protective FET that is already used for charge/discharge protection.

Ideal diode function implemented with existing battery protection FETs

A modulated light source comprises a laser diode and a drive circuit coupled operatively to the laser diode. The laser diode is configured to lase upon passing an above-threshold current for an accumulation period. The drive circuit is configured to draw a priming current through the laser diode over a priming period, the priming current being insufficient to cause the laser diode to lase during the priming period, but sufficient to shorten the accumulation period. The drive circuit is further configured to draw the above-threshold current through the laser diode after the priming period, thereby triggering emission from the laser diode following a shortened accumulation period.

Laser diode priming to reduce latency

A system for dynamically adjusting a bias voltage for a laser diode or a light emitting diode is provided. An output voltage of the laser diode is measured and a level of a supply voltage applied to the laser diode is adjusted to change the bias voltage to the laser diode to manage power usage and avoid saturation of the laser diode. Also, a junction temperature of a laser diode may be estimated by mapping a measured output voltage and known current to device characteristic data based on temperature and the supply voltage adjusted in order to bias the laser diode to compensate for a temperature change. Further, data indicating an intensity level of data to be rendered by the laser diode is used to adjust the second supply voltage to bias the laser diode in advance of rendering the data.

Dynamic supply voltage control circuit for laser diode

A gated time of flight (GT-TOF) range camera that transmits a plurality of light pulses to illuminate features in a scene and gates ON a photosensor in the camera for one multi-exposure gate having a plurality of exposure periods following each of the plurality of light pulses to register amounts of light reflected by features in the scene from the light pulses and uses the registered amounts of light to determine distances to the features.

Extended range gated time of flight camera

A GT-TOF camera that illuminates a scene with a train of light pulses to determine amounts of light reflected from the transmitted light pulses by features in a scene for each of N different exposure periods and determines a distance to a feature in the scene responsive to a direction in an N-dimensional space of an N-dimensional vector defined by the amounts of reflected light determined for the feature for the N gates.

Gated time of flight camera

Embodiments disclosed herein are directed to time-of-flight (TOF) systems, and methods for use therewith, that substantially reduce interference that the TOF system may cause to at least one other system that is configured to wirelessly receive and respond to IR light signals. Some such embodiments involve emitting IR light having a low frequency (LF) power envelope that is shaped to substantially reduce frequency content within at least one frequency range known to be used by at least one other system that may be in close proximity to the TOF system. Such embodiments can also involve detecting at least a portion of the emitted RF modulated IR light that has reflected off one or more objects. A TOF system can produce depth images in dependence on results of the detecting, as well as update an application in dependence on the depth images.

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Fall City, WA, United States of America

Algird Michael Gudaitis