An additive manufacturing apparatus includes a laser and a detection system. The laser emits a laser beam to heat a powder bed to form a melt pool, and the melt pool emits light proportional to a temperature of the melt pool. The detection system includes a spectral disperser and one of a) two or more on-axis sensors or b) a line scanner. The two or more on-axis sensors or the line scanner are/is located along an axis of the emitted light, the detection system receives the emitted light from the melt pool, and an intensity of the emitted light detected by the a) two or more on-axis sensors or the b) line scanner is compared with a blackbody spectral map at a particular wavelength of the emitted light to determine a temperature of the melt pool.

A thermal radiation light detection device includes: a housing including a plurality of wall portions; a light entrance unit attached to a wall portion and configured to cause thermal radiation light to enter the housing; a light extraction unit disposed inside housing and configured to extract light of a first wavelength and light of a second wavelength from the thermal radiation light, the second wavelength being different from the first wavelength; a first light detection unit attached to a wall portion and configured to detect the light of the first wavelength; a second light detection unit attached to a wall portion and configured to detect the light of the second wavelength; and a first temperature detection unit attached to a wall portion, the wall portion to which the first temperature detection unit is attached being different from the wall portion to which the first light detection unit is attached.

A non-contact temperature sensor (1) suitable for use in measuring the temperature of a material blank (3). The temperature sensor (1) comprises a housing (5), an opening (7) at the forward end of the housing (5), a reflector (13) that is located within the housing (5), at least one aperture (15) that is located between the forward surface and the rearward surface of the reflector (13) and a light detector arrangement (17) located rearward of the reflector (13). The light detector arrangement (17) is orientated such that it can receive light passing through the at least one aperture (15) and it is capable of detecting at least two ranges of wavelengths of infrared light. The light detector arrangement (17) outputs data for each of the at least two ranges of wavelengths of infrared light.

An infrared photodetection system is provided that is capable of measuring infrared light up to high-temperature regions while improving a temperature resolution for low-temperature regions without increasing image-acquisition time even if the measuring temperature range varies. The infrared photodetection system is set up to exhibit sensitivity spectrum SSP1 for high sensitivity (for low temperature use) and sensitivity spectrum SSP2 for low sensitivity (for high temperature use) in the transmission band of the bandpass filter when different voltages are applied to a quantum-dot infrared photodetector. The infrared photodetection system then integrates temperature data for the infrared light detected using sensitivity spectrum SSP1 and temperature data for the infrared light detected using sensitivity spectrum SSP2, in order to output a temperature distribution in a measurement region.

A first radiance meter is directed toward an object to be measured, radiance is measured through a space where dust is present with the use of at least two wavelengths by the first radiance meter, second radiance meters which are equal in number to one or more objects having temperatures different from that of the object to be measured are directed toward the objects, radiances are measured through the space with the use of at least two wavelengths by the second radiance meters respectively, and a temperature of the object to be measured, a temperature of the dust, and concentration of the dust are measured from the radiances measured by the first radiance meter and the second radiance meters.

A method includes capturing an image, and performing region detection on the captured image. The region detection includes identifying an object represented in the captured image. The method further includes detecting emissivity of the identified object and determining the temperature of the object based on the detected emissivity of the object.

A first radiance meter is directed toward an object to be measured, radiance is measured through a space where dust is present with the use of at least two wavelengths by the first radiance meter, second radiance meters which are equal in number to one or more objects having temperatures different from that of the object to be measured are directed toward the objects, radiances are measured through the space with the use of at least two wavelengths by the second radiance meters respectively, and a temperature of the object to be measured, a temperature of the dust, and concentration of the dust are measured from the radiances measured by the first radiance meter and the second radiance meters.

An additive manufacturing temperature controller/temperature sensor uses one or more spectrophotometric sensors to monitor temperature of successive layers and preferably localized sections of successive layers of a melt pool, and transients thereof, of an object being generated for the purpose of dynamic control of the additive manufacturing device and/or quality control of the generated object manufactured with the additive manufacturing device. Generally, the additive manufacturing temperature controller/sensor apparatus monitors temperature of a section of the object during manufacture as a function of wavelength, time, position, and/or angle to determine melt extent in terms of radius and/or depth.

A system and method for processing a daytime IR image to discriminate between solar glints and hotspots, where the latter represent man-made activity. Two spectrally distinct thermal wavelength bands are defined and respective spectral intensities are detected for a corresponding pixel in an image. A figure of merit is calculated as a function of the detected spectral intensities. The calculated figure of merit is compared to a predetermined rule to determine whether the corresponding pixel is a glint or a hotspot.

An infrared photodetection system is provided that is capable of measuring infrared light up to high-temperature regions while improving a temperature resolution for low-temperature regions without increasing image-acquisition time even if the measuring temperature range varies. The infrared photodetection system is set up to exhibit sensitivity spectrum SSP1 for high sensitivity (for low temperature use) and sensitivity spectrum SSP2 for low sensitivity (for high temperature use) in the transmission band of the bandpass filter when different voltages are applied to a quantum-dot infrared photodetector. The infrared photodetection system then integrates temperature data for the infrared light detected using sensitivity spectrum SSP1 and temperature data for the infrared light detected using sensitivity spectrum SSP2, in order to output a temperature distribution in a measurement region.