38results about "Photoelectric exposure meters" patented technology

A radiometer and method for providing an indication of the amount of time (exposure duration) needed to cause a light curable dental resin composite material to maximally polymerize in response to the application of light from any light-curing source during the preparation of a dental restoration. It describes a radiometer comprising a sample holder of a size designed to hold a sample equivalent of said dental light curable dental material such that the thickness of the sample of light curable material in the sample holder will correspond to the depth of the composite material in the dental restoration; a solid state light sensor; a microprocessor programmed to respond to the output voltage or change in electrical resistance of the light sensor based upon an algorithm defining a mathematical model representative of the change in light transmission through the light curable dental material as a function of the degree to which said light curable dental material is being polymerized. It includes a time display that is responsive to the output signal generated from the microprocessor for displaying the amount of time (exposure duration) needed to maximally polymerize the light curable dental material in the dental restoration.

An optical sensor includes a light-emitting element for directing light to an image, a light-receiving element for receiving light reflected by the image, a normal detection optical path for allowing the light emitted by the light-emitting element and the light reflected from the image to follow a normal detection optical path during normal operation, a calibration reflecting plate disposed inside the optical sensor for reflecting light from the light-emitting element when sensitivity is calibrated, a calibration optical path for allowing the light emitted by the light-emitting element to follow a calibration optical path to the light-receiving element when the emitted light is reflected by the calibration reflecting plate, and a first optical function element disposed in the calibration optical path and switchable between a light permeating state, in which the light passes therethrough, and a light intercepting state, in which the light is blocked, when voltage is applied.

In order to measure a characteristics of a light beam which is repetitively deflected by a light scanning device within a first range in a first direction at a first velocity, there is provided a plate formed with at least one slit extending in a direction angled from the first direction and having a constant width. The plate is moved within the first range in the first direction at a second velocity which is sufficiently lower than the first velocity. A peak value of an optical power of light passing through the slit every time is detected when the deflected light beam crosses the slit being moved, thereby obtaining peak values at plural positions in the first direction. The peak values are displayed on a screen collectively in such a manner that positions on the screen correspond to the positions in the first direction.

This invention discloses a printing quality inspection apparatus including a light irradiation device, an image capture device, a diffusely reflecting plate, and a determination device. When a member to be printed is a first sheet member, light emitted by the light irradiation device is diffusely reflected by the first sheet member and enters the image capture device. When the member to be printed is a second sheet member, the light emitted by the light irradiation device is diffusely reflected by the diffusely reflecting plate, is specularly reflected by the second sheet member, and enters the image capture device.

An optical sensor includes a first LED, a second LED, a first PD, and a second PD. The first LED and the second LED are configured to irradiate an optical-axis center point of an intermediate transfer belt. The first PD is arranged at a position at which specularly reflected light of light emitted from the first LED and diffused reflected light of light emitted from the second LED are received. The second PD is arranged at a position at which diffused reflected light of the light emitted from the first LED is received.

A focus detection apparatus that performs phase difference focus detection based on signals of a plurality of colors obtained from an image sensor, which is covered by color filters of the plurality of colors, that performs photoelectric conversion on light incident on the image sensor via an imaging optical system and outputs electric signals, the apparatus comprising: an acquisition unit that acquires an addition coefficient indicating weights to be applied to the signals of the plurality of colors on the basis of characteristic of chromatic aberration of magnification of the imaging optical system; a generation unit that generates a pair of focus detection signals by performing weighted addition on the signals of the plurality of colors using the addition coefficient; and a detection unit that detects an image shift amount between the pair of focus detection signals.

The invention relates to a vision inspection apparatus and a method of driving the vision inspection apparatus, the visual inspection apparatus comprising: an inspection controller that displays a grid pattern having a plurality of gray scales on a display panel; an imaging converter that drives the charge-coupled device with a predetermined or set exposure time and converts a grid pattern displayed on the display panel into a grid pattern signal; a charger calculator that calculates an amount of charge per unit time of each color of the reference grayscale using the reference grayscale signalincluded in the raster pattern signal and the set exposure time; and an exposure time calculator that calculates an optimal exposure time for each color of the reference gray scale based on the target charge amount of the reference gray scale.

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.

An image capturing apparatus comprises: a photometry unit configured to perform photometry on a subject and output a photometric value; an obtaining unit configured to obtain a plurality of photometric values from the photometry unit during a predetermined period of time; and a calculation unit configured to perform a prediction calculation to predict a luminance of the subject based on the plurality of photometric values obtained by the obtaining unit.

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.