A device for simply determining maximum permissible exposure time (MPE) of retina is disclosed, which principally comprises a light receiving unit and a core processor that is provided with a color temperature determining unit, a luminous flux determining unit and a calculating unit therein. The color temperature determining unit and the luminous flux determining unit are configured for completing a color temperature determination and a luminous flux determination of a light provided by a light source, respectively. The calculating unit is configured for calculating a maximum permissible exposure time (MPE) of retina of the light source based on a use distance and a color temperature and a luminous flux of the light. By using this device, generic users are facilitated to achieve the calculation of any one kind of light's MPE by themselves, without needing to using any spectrometer.

The present invention includes an imager 1 having an automatic exposure stopping function, which are implemented therein, and includes an exposure time measuring unit 24 to measure the exposure time from the start of exposure to the stopping of exposure in the imager 1, a measurement distance calculating unit 21 to calculate the measurement distance to an object M on the basis of a displacement of the light receiving position in the imager 1, and a data output/storage unit 25 to output and/or store, as data related with acquisition of a distance actual value, which is an actual distance to the object, in a condition in which the measured exposure time and the measurement distance calculated with this exposure time are associated with each other.

A light sensor having an adaptively controlled gain includes a photoelectric element, an operational amplifier, a comparator, an adaptive gain control circuit, a variable capacitor and a pulse accumulator circuit. The photoelectric element converts light energy into a photocurrent. The operational amplifier outputs an error amplified signal based on a gain multiplied by a voltage difference between an input voltage and a reference voltage. The comparator compares the error amplified signal with a voltage of a reference voltage source to output a comparison signal. The adaptive gain control circuit includes a pulse detector circuit and a gain control circuit. The pulse detector circuit detects the comparison signal and a clock signal to output a pulse detected signal. The adaptive gain control circuit outputs a capacitance modulating signal according to the pulse detected signal. A capacitance of the variable capacitor is modulated according to the capacitance modulating signal.

A device for simply determining maximum permissible exposure time (MPE) of retina is disclosed, which principally comprises a light receiving unit and a core processor that is provided with a color temperature determining unit, a luminous flux determining unit and a calculating unit therein. The color temperature determining unit and the luminous flux determining unit are configured for completing a color temperature determination and a luminous flux determination of a light provided by a light source, respectively. The calculating unit is configured for calculating a maximum permissible exposure time (MPE) of retina of the light source based on a use distance and a color temperature and a luminous flux of the light. By using this device, generic users are facilitated to achieve the calculation of any one kind of light's MPE by themselves, without needing to using any spectrometer.

A vision inspection apparatus includes an inspection controller which displays a grid pattern with a plurality of gray levels on a display panel, an imaging converter which drives a charge-coupled device with a predetermined or set exposure-time and converts the grid pattern displayed on the display panel into a grid pattern signal, a charge calculator which calculates a charge amount per unit time for each color of a reference gray level using a reference gray level signal, included in the grid pattern signal, and the set exposure-time, and an exposure-time calculator which calculates an optimum exposure-time for each color of the reference gray level based on a target charge amount of the reference gray level.

To calculate a probability of an optical sensor's irregular discharge, a light detection system includes an optical sensor, an application voltage generating circuit that applies a drive pulse voltage to the optical sensor, a discharge determining portion that detects the optical sensor's discharge, a discharge probability calculating portion that calculates a discharge probability for each of first and second states in which the optical sensor is shielded from light and the drive pulse voltage's width in the second state is different from the first state, a sensitivity parameter storing portion storing the drive pulse voltage's reference pulse width as the optical sensor's sensitivity parameter, and another discharge probability calculating portion that calculates an irregular discharge's probability that occurs without depending on the optical sensor's received light quantity, based on the sensitivity parameter, and the discharge probabilities calculated and the drive pulse voltage's widths in the first and second states.

To calculate a probability of an optical sensor's irregular discharge, a light detection system includes an optical sensor, an application voltage generating circuit that applies a drive pulse voltage to the optical sensor, a discharge determining portion that detects the optical sensor's discharge, a discharge probability calculating portion that calculates a discharge probability for each of first and second states in which the optical sensor is shielded from light and the drive pulse voltage's width in the second state is different from the first state, a sensitivity parameter storing portion storing the drive pulse voltage's reference pulse width as the optical sensor's sensitivity parameter, and another discharge probability calculating portion that calculates an irregular discharge's probability that occurs without depending on the optical sensor's received light quantity, based on the sensitivity parameter, and the discharge probabilities calculated and the drive pulse voltage's widths in the first and second states.

One variation of a system for tracking and responding to Sun exposure includes: a housing configured to transiently attach to a port on a first garment; a jack coupled to the housing configured to transiently engage a port on the first garment; a radiation sensor arranged in the housing and configured to detect solar radiation incident on the housing; and a controller configured to: read an identifier of the first garment from the port via the jack; based on the identifier, estimate a skin exposure of a user wearing the first garment; read a solar radiation value from the radiation sensor at a first time; and, based on the solar radiation value and the skin exposure, estimate a solar radiation exposure of the user at the first time.

A vision inspection apparatus includes an inspection controller which displays a grid pattern with a plurality of gray levels on a display panel, an imaging converter which drives a charge-coupled device with a predetermined or set exposure-time and converts the grid pattern displayed on the display panel into a grid pattern signal, a charge calculator which calculates a charge amount per unit time for each color of a reference gray level using a reference gray level signal, included in the grid pattern signal, and the set exposure-time, and an exposure-time calculator which calculates an optimum exposure-time for each color of the reference gray level based on a target charge amount of the reference gray level.

A medical device is configured to monitor, using one or more sensors, an environmental condition of a physical environment proximate to a medical device, and to determine when a value representative of the environmental condition exceeds a threshold for safe operation of the medical device with regard to care of a patient. Responsive to the value exceeding the threshold, an operation mode of the medical device is automatically switched from a first mode currently programmed for the care of the patient to a second mode, the second mode using different parameters than the first mode to control the medical device.