Abstract: In some embodiments, a method includes: selecting dimensions of a slot to be provided in a device feature, the dimensions selected to accommodate one or more tools while resulting in tangential contact between the slot and the one or more tools when the one or more tools are inserted into the slot and used to manipulate the device feature; and forming the slot in a surface of the device feature according to the selected dimensions.

Abstract: A spring damper device comprising a directional spring (e.g., coil) having first and second ends, and defining an inner diameter region. A damper (e.g., viscoelastic polymer slug) comprising an element of elasticity configured to be situated within the inner diameter region of the directional spring. In response to a load on the spring damper device, the directional spring operates to compress, and the damper operates to dampen vibration associated with the load. The damper can comprise a viscoelastic damper comprising both an element of viscosity and the element of elasticity. The damper can be substantially coaxially aligned with the directional spring. Spring damper device(s) can be preloaded in a micro adjustment mechanism to account for positional adjustments between two structures (e.g., between a scope and a firearm), such that the spring(s) attenuate a shock impulse event (e.g., when firing), while the damper(s) attenuate vibration (e.g., to prevent damage the scope).

Abstract: A variable magnification optical system with boresight error correction includes a focusing lens to receive light along an optical axis of the variable magnification optical system, with the focusing lens configured to create an image of a target at a focal plane. The system includes a magnification changer disposed along the optical axis, with the magnification changer including an optomechanical drive system to adjust an optical magnification setting of one or more zoom lenses. The system also includes a light source configured to emit a pilot beam into the magnification changer. The system includes a position sensitive photodetector configured to receive the pilot beam exiting the magnification changer. The system further includes a microdisplay optically conjugate to the focal plane, with the microdisplay configured to impose an image of an electronic reticle on the focal plane based on the position of the pilot beam relative to the position sensitive photodetector.

Abstract: An apparatus includes one or more light emitting diodes (LEDs) configured to be coupled to a power supply and to generate illumination, such as to generate a reticle in an optical scope. The apparatus also includes a first switch coupled in series with the one or more LEDs. The first switch is configured to selectively activate and deactivate the one or more LEDs based on whether the first switch is turned on or off. The apparatus further includes a low power detector configured to sense a low power condition of the power supply and to repeatedly turn the first switch on and off in response to the low power condition to cause the one or more LEDs to blink. The low power detector is configured to turn the first switch on and off at a given rate, and the given rate increases as the power supply is depleted.

Abstract: An apparatus for rotary encoding includes a knob configured to be rotated. The apparatus also includes multiple switches each configured to selectively form or not form a connection based on a current rotational position of the knob. The apparatus further includes a controller configured to generate or use a digital value associated with the current rotational position of the knob. The digital value is defined by which switches have or have not formed connections. Locations where the switches form the connections are selected such that the digital values uniquely identify different rotational positions of the knob and are non-sequential as the knob is rotated.

Abstract: A spring damper device comprising a directional spring (e.g., coil) having first and second ends, and defining an inner diameter region. A damper (e.g., viscoelastic polymer slug) comprising an element of elasticity configured to be situated within the inner diameter region of the directional spring. In response to a load on the spring damper device, the directional spring operates to compress, and the damper operates to dampen vibration associated with the load. The damper can comprise a viscoelastic damper comprising both an element of viscosity and the element of elasticity. The damper can be substantially coaxially aligned with the directional spring. Spring damper device(s) can be preloaded in a micro adjustment mechanism to account for positional adjustments between two structures (e.g., between a scope and a firearm), such that the spring(s) attenuate a shock impulse event (e.g., when firing), while the damper(s) attenuate vibration (e.g., to prevent damage the scope).

Abstract: An apparatus for rotary encoding includes a knob configured to be rotated. The apparatus also includes multiple switches each configured to selectively form or not form a connection based on a current rotational position of the knob. The apparatus further includes a controller configured to generate or use a digital value associated with the current rotational position of the knob. The digital value is defined by which switches have or have not formed connections. Locations where the switches form the connections are selected such that the digital values uniquely identify different rotational positions of the knob and are non-sequential as the knob is rotated.

Abstract: An apparatus includes one or more light emitting diodes (LEDs) configured to be coupled to a power supply and to generate illumination, such as to generate a reticle in an optical scope. The apparatus also includes a first switch coupled in series with the one or more LEDs. The first switch is configured to selectively activate and deactivate the one or more LEDs based on whether the first switch is turned on or off. The apparatus further includes a low power detector configured to sense a low power condition of the power supply and to repeatedly turn the first switch on and off in response to the low power condition to cause the one or more LEDs to blink. The low power detector is configured to turn the first switch on and off at a given rate, and the given rate increases as the power supply is depleted.

Abstract: Aspects are generally directed to a high speed pupil detection system and method. In one example, the method includes receiving optical radiation reflected from an eye at one or more pixels of an optical sensor, reading-out a value of each of the pixels in a plurality of lines to progressively generate an image frame of a video image stream, the value of each of the pixels being based on a flux of the received optical radiation, identifying a first chord within a first line of the plurality of lines, identifying a second chord within a second line of the plurality of lines, the first chord and second chord being separated by a subset of the plurality of lines, and determining a location of a center of a pupil of the eye based on a two chord crossing of the pupil with the first chord and the second chord.

Abstract: Aspects are generally directed to a high speed pupil detection system and method. In one example, the method includes receiving optical radiation reflected from an eye at one or more pixels of an optical sensor, reading-out a value of each of the pixels in a plurality of lines to progressively generate an image frame of a video image stream, the value of each of the pixels being based on a flux of the received optical radiation, identifying a first chord within a first line of the plurality of lines, identifying a second chord within a second line of the plurality of lines, the first chord and second chord being separated by a subset of the plurality of lines, and determining a location of a center of a pupil of the eye based on a two chord crossing of the pupil with the first chord and the second chord.

Abstract: A pulse-width modulation (PWM) light source drive for driving a light source is provided that includes a microcontroller, a modulation element, a voltage regulator, and a light detector. The microcontroller is configured to generate a PWM signal and an inverse PWM signal. The modulation element is configured to generate a drive signal based on the PWM signal. The light source is configured to be driven by the drive signal. The voltage regulator is configured to generate an output drive voltage for the light source. The light detector is configured to detect light energy emitted by the light source, to generate an optical power feedback signal based on the detected light energy, and to provide the optical power feedback signal to the voltage regulator during a laser-on driving interval. The microcontroller is configured to provide the inverse PWM signal to the voltage regulator during a laser-off driving interval.

Abstract: A pulse-width modulation (PWM) light source drive for driving a light source is provided that includes a microcontroller, a modulation element, a voltage regulator, and a light detector. The microcontroller is configured to generate a PWM signal and an inverse PWM signal. The modulation element is configured to generate a drive signal based on the PWM signal. The light source is configured to be driven by the drive signal. The voltage regulator is configured to generate an output drive voltage for the light source. The light detector is configured to detect light energy emitted by the light source, to generate an optical power feedback signal based on the detected light energy, and to provide the optical power feedback signal to the voltage regulator during a laser-on driving interval. The microcontroller is configured to provide the inverse PWM signal to the voltage regulator during a laser-off driving interval.

Abstract: A tactile feel control device is disclosed. The tactile feel control device can include an electric motor configured to be mechanically coupled to a manual control interface that is movable by a user. The tactile feel control device can also include a bias module operable to generate a bias to be applied by the electric motor. The bias can be configured to provide a desired tactile feel to the user at the manual control interface. In addition, the tactile feel control device can include a control module operable to output a drive signal to the electric motor configured to apply the bias. The bias can be insufficient, alone, to cause movement of the manual control interface.

Abstract: A tactile feel control device is disclosed. The tactile feel control device can include an electric motor configured to be mechanically coupled to a manual control interface that is movable by a user. The tactile feel control device can also include a bias module operable to generate a bias to be applied by the electric motor. The bias can be configured to provide a desired tactile feel to the user at the manual control interface. In addition, the tactile feel control device can include a control module operable to output a drive signal to the electric motor configured to apply the bias. The bias can be insufficient, alone, to cause movement of the manual control interface.