Abstract: A system is provided for maintaining a safe operating area while also providing a suitable forward bias voltage to drive a laser diode. The system can monitor a voltage that is applied to a laser diode driver using a threshold that is based on the fabrication process of the laser diode driver. For example, a system can utilize a first threshold for a laser diode driver that is fabricated utilizing a 10 nm process and utilize a second threshold for another laser diode driver that is fabricated utilizing a 20 nm process. The threshold can also be based on a color of the laser or a desired operation mode. The system can monitor a voltage applied to a laser diode using different thresholds while controlling a bleed current to ensure that the laser diode is forward biased while mitigating the risk of silicon breakdown of the laser diode driver.

Abstract: Examples are disclosed that relate to determining a capacitance based on a charge accumulated on a sense capacitor electrode. One example provides a head-mounted device comprising a facial-tracking sensor, a controller, and a charge sensing circuit connected to the facial-tracking sensor. The facial-tracking sensor comprises a sense capacitor electrode configured to be positioned proximate to a surface of a face and form a capacitance based upon a distance between the sense capacitor electrode and the surface of the face, and the controller configured to apply a reference voltage to the sense capacitor electrode. The charge sensing circuit is configured to determine the capacitance of the sense capacitor electrode by determining an amount of charge accumulated on the sense capacitor electrode resulting from the reference voltage.

Abstract: A display device includes a display substrate and a backplane substrate. The display substrate includes an array of micro-LEDs forming individual pixels. The backplane substrate includes a plurality of pixel logic hardware modules. Each pixel logic hardware module includes a local memory element configured to store a multi-bit pixel intensity value of a corresponding micro-LED for an image frame. The backplane substrate is bonded to a backside of the display substrate such that the pixel logic hardware modules are physically aligned behind the array of micro-LEDs and each pixel logic hardware module is electrically connected to a micro-LED of the corresponding pixel.

Abstract: A display device includes a display substrate and a backplane substrate. The display substrate includes an array of micro-LEDs forming individual pixels. The backplane substrate includes a plurality of pixel logic hardware modules. Each pixel logic hardware module includes a local memory element configured to store a multi-bit pixel intensity value of a corresponding micro-LED for an image frame. The backplane substrate is bonded to a backside of the display substrate such that the pixel logic hardware modules are physically aligned behind the array of micro-LEDs and each pixel logic hardware module is electrically connected to a micro-LED of the corresponding pixel.

Abstract: A display device includes a display substrate and a backplane substrate. The display substrate includes an array of micro-LEDs forming individual pixels. The backplane substrate includes a plurality of pixel logic hardware modules. Each pixel logic hardware module includes a local memory element configured to store a multi-bit pixel intensity value of a corresponding micro-LED for an image frame. The backplane substrate is bonded to a backside of the display substrate such that the pixel logic hardware modules are physically aligned behind the array of micro-LEDs and each pixel logic hardware module is electrically connected to a micro-LED of the corresponding pixel.

Abstract: Technologies are described herein for an eye tracking that may be employed by devices and systems such as head mount display (HMD) devices. Light that is reflected from a user's eye may be specular or scattered. The specular light has an intensity or magnitude that may saturate the electronics. The presently disclosed techniques mitigate saturation by generating detected signals from an optical detector, evaluating the signal levels for the detected signal, and selectively gating the detected signals that have saturated. The remaining scattered signals can be combined to achieve a combined signal that can be converted into a digital signal without saturating the electronics, which can then be processed to form an image of the eye for identification purposes, for tracking eye movement, and for other uses. The described technologies provide a clear image without ambient light reflections or specular light interfering with the image.

Abstract: Technologies are described herein for an eye tracking that may be employed by devices and systems such as head mount display (HMD) devices. Light that is reflected from a user's eye may be specular or scattered. The specular light has an intensity or magnitude that may saturate the electronics. The presently disclosed techniques mitigate saturation by generating detected signals from an optical detector, evaluating the signal levels for the detected signal, and selectively gating the detected signals that have saturated. The remaining scattered signals can be combined to achieve a combined signal that can be converted into a digital signal without saturating the electronics, which can then be processed to form an image of the eye for identification purposes, for tracking eye movement, and for other uses. The described technologies provide a clear image without ambient light reflections or specular light interfering with the image.

Abstract: A system is provided for maintaining a safe operating area while also providing a suitable forward bias voltage to drive a laser diode. The system can monitor a voltage that is applied to a laser diode driver using a threshold that is based on the fabrication process of the laser diode driver. For example, a system can utilize a first threshold for a laser diode driver that is fabricated utilizing a 10 nm process and utilize a second threshold for another laser diode driver that is fabricated utilizing a 20 nm process. The threshold can also be based on a color of the laser or a desired operation mode. The system can monitor a voltage applied to a laser diode using different thresholds while controlling a bleed current to ensure that the laser diode is forward biased while mitigating the risk of silicon breakdown of the laser diode driver.

Abstract: 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.

Abstract: 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.