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: 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 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.