Methods and devices determine an eye strain indicator. In one aspect, an augmented reality (AR) device wearable by a user includes an image sensor and a processor coupled to the image sensor. The processor receives image data from the image sensor, determine that a display is within a field of view (FOV) of the AR device, determine an eye strain indicator based on the determination that the display is within the FOV of the AR device, and provide the eye strain indicator to the user.

A data output device is provided. The data output device includes a converter circuit configured to generate a conversion signal based on an output signal; a boosting circuit configured to generate a boosting signal based on the output signal; and an output circuit configured to generate the output signal based on an input signal and a feedback signal, the feedback signal being based on the conversion signal and the boosting signal.

The air condition measurement apparatus according to various embodiments of the present invention comprises: a housing comprising a first space and a second space therein; a light-emitting unit which is positioned inside the housing, comprises a first lens, and radiates light to air flowing into the housing; a light-receiving unit which is positioned inside the housing, comprises a second lens, and receives reflected light formed from the reflection of the radiated light, radiated from the light-emitting unit, by foreign substances included in the air; a blocking member which transmits the radiated light or the reflected light and separates the first space, in which the light-emitting unit or the light-receiving unit is disposed, from the second space; and a control unit, wherein the control unit may be configured to measure the condition of air on the basis of a signal corresponding to the reflected light received by the light-receiving unit. Other various embodiments may be possible.

A method for locating a center of a field of view of an optical element using a system having a surface disposed at a first illumination, an image receiver, a blocker disposed at a second illumination, the method including disposing the blocker at, at least one location in the field of view upon the surface in a first direction when the brightness of an image within the field of view of the optical element is disposed at a brightness and recording a first location of the blocker; repeating the disposing step in a second direction and at the brightness, wherein the second direction is opposite the first direction and each of the first direction and the second direction is parallel to the surface; and averaging the first location and the second location to yield the center of the field of view of the optical element in the first direction.

A method for locating a center of a field of view of an optical element using a system having a surface disposed at a first illumination, an image receiver, a blocker disposed at a second illumination, the method including disposing the blocker at, at least one location in the field of view upon the surface in a first direction when the brightness of an image within the field of view of the optical element is disposed at a brightness and recording a first location of the blocker; repeating the disposing step in a second direction and at the brightness, wherein the second direction is opposite the first direction and each of the first direction and the second direction is parallel to the surface; and averaging the first location and the second location to yield the center of the field of view of the optical element in the first direction.

A sensor circuit comprising a sensor input includes a delta-sigma analogue to digital converter. The delta-sigma analogue to digital converter includes a switched capacitor, a common mode voltage source, a reference voltage source, and a switch network. The switch network, in a first clock phase, connects the switched capacitor to charge it to either a sum or difference voltage, and in a second clock phase connects the switched capacitor to transfer charge into a summing junction. A controller controls the switch network responsive to a comparator output to selectively connect the switched capacitor to one of the common mode voltage and the reference voltage in the first clock phase. Implementations of the sensor circuit transfer charge every clock cycle and have low noise and high sensitivity.

A sensor circuit comprising a sensor input includes a delta-sigma analogue to digital converter. The delta-sigma analogue to digital converter includes a switched capacitor, a common mode voltage source, a reference voltage source, and a switch network. The switch network, in a first clock phase, connects the switched capacitor to charge it to either a sum or difference voltage, and in a second clock phase connects the switched capacitor to transfer charge into a summing junction. A controller controls the switch network responsive to a comparator output to selectively connect the switched capacitor to one of the common mode voltage and the reference voltage in the first clock phase. Implementations of the sensor circuit transfer charge every clock cycle and have low noise and high sensitivity.

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium that automatically performs actions in an aquaculture environment based on light sensed by underwater cameras. One of the methods includes obtaining images of a surface of water captured by a camera that faces upwards from a depth towards the surface of the water within an enclosure that encloses aquatic livestock. An ambient light metric is determined at the depth from the images of the surface of the water. A determination is made as to whether the camera satisfies one or more depth criteria. Based on determining that the depth of the camera satisfies the one or more depth criteria, it is determined that, based on the ambient light metric at the depth, one or more action criteria are satisfied, then initiating performance of an action to be performed for the aquatic livestock.

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium that automatically performs actions in an aquaculture environment based on light sensed by underwater cameras. One of the methods includes obtaining images of a surface of water captured by a camera that faces upwards from a depth towards the surface of the water within an enclosure that encloses aquatic livestock. An ambient light metric is determined at the depth from the images of the surface of the water. A determination is made as to whether the camera satisfies one or more depth criteria. Based on determining that the depth of the camera satisfies the one or more depth criteria, it is determined that, based on the ambient light metric at the depth, one or more action criteria are satisfied, then initiating performance of an action to be performed for the aquatic livestock.

A photoelectric conversion apparatus includes a pixel including a photoelectric conversion circuit configured to output a signal corresponding to photon incidence. The photoelectric conversion apparatus further includes a first measurement circuit, an addition circuit, and a second measurement circuit. The first measurement circuit is configured to measure the signal output from the pixel. The addition circuit is configured to add measured values of a plurality of the first measurement circuits. The second measurement circuit is configured to measure a time from when each of the plurality of first measurement circuits starts measuring the signal to when the measured values added by the addition circuit reach a first threshold value.