Ultraviolet (UV) light emission devices and related methods of use. The UV light emission devices disclosed herein are particularly suited for use in disinfecting surfaces and air. The UV light emission devices disclosed herein can be provided in the form factor of a handheld device that is easily held and manipulated by a human user. The human user can manipulate the handheld UV light emission device to decontaminate surfaces, air, and other areas by orienting the handheld UV light emission device so that the UV light emitted from its light source is directed to the area of interest to be decontaminated.

A UV exposure dosimetry system includes at least one UV sensor that measures the UV irradiance intensity. The system can generate extrapolated UV intensity data based on measured UV intensity data to correct unreliable UV measurement due to inconsistent irradiation of UV light. The system integrates the extrapolated UV intensity data over time to calculate real-time UV dosage and vitamin D production by taking into account factors including UV sensor location, body surface area, clothing coverage, and sunscreen usage. Based on the measurement, the system can predict the time remaining to skin burn and the time remaining to reach daily goal of vitamin D production. The system is also adapted to measure sun exposure time based on the corrected UV intensity over a period of time. The UV dosimetry system supports multi-user control through an advanced and user friendly input and output interface.

To calculate received light quantity even when part of noise component's discharge probability is unknown, a light detection system includes a discharge probability calculating portion that calculates discharge probabilities for a first state in which a source's light with known light quantity impinges on an optical sensor, a second state in which the source's turning-on/turning-off state is the same as the first state with a drive pulse width applied to the optical sensor different from the first state, a third state in which the source's turning-on/turning-off state is different from the first and second states with the same pulse width as the first state, and a fourth state in which the source's turning-on/turning-off state is the same as the third state with the same pulse width as the second state, another discharge probability calculating portion that calculates regular and irregular discharges' probabilities, and a received light quantity calculating portion.

An instrumented substrate apparatus is configured to measure wavelength-resolved radiation, such as extreme ultraviolet radiation. The instrumented substrate apparatus includes a substrate and photoelectric sensors on the substrate. The photoelectric sensors include a photoemissive material, a photoelectron collector, and a measurement circuit. The measurement circuit is electrically coupled to the photoemissive material and the photoelectron collector. The measurement circuit is configured to measure a current generated by the photoelectron collectors by a current meter. Such current is used to determine the wavelength-resolved EUV measurement information by a controller on the instrumented substrate apparatus, or by communicating the current to a factory automation system.

In accordance with at least one aspect of this disclosure, an ultraviolet radiation (UV) sensor includes a UV sensitive material and a first electrode and a second electrode connected in series through the UV sensitive material such that UV radiation can reach the UV sensitive material. The UV sensitive material can include at least one of zinc tin oxide, magnesium oxide, magnesium zinc oxide, or zinc oxide. The electrodes can be interdigitated comb electrodes.

The invention provides systems and methods for wearable and tissue-mounted electronics for monitoring exposure of a subject or object to electromagnetic radiation, particularly electromagnetic radiation in the visible, ultraviolet and infrared portions of the electromagnetic spectrum. In some embodiments, the devices are purely passive devices where absorption of incident electromagnetic radiation by the device provides at least a portion of the power for the measurement of the radiant exposure or flux of the incident electromagnetic radiation. Devices of the invention may include near field communication components, for example, for enabling readout by an external device, such as a computer or mobile device.

The invention relates to a device and a method for determining a wavelength of radiation.

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 system, apparatus and method of improved measurement of the SPF factor of sunscreen compositions. In one embodiment, a method of measuring the protection of a sunscreen composition includes exposing skin to a known intensity of light, measuring the amount of remitted light from the skin, applying sunscreen to the skin, exposing the skin to which the sunscreen has been applied the known intensity of emitted light of the spectrum of light from which the sunscreen is intended to protect the skin, measuring the amount of light remitted from the skin, and calculating a UltraViolet-A Protection Factor (UVA-PF) of the sunscreen by comparing the amount of light remitted from the skin with the sunscreen to the amount of light remitted from the skin without the sunscreen.

A flame or gas detection method includes determining non-imaging sensor system detection state for a scene of interest, determining an imaging sensor system detection state for the scene of interest, and validating one of the non-imaging sensor system detection state and the imaging sensor system detection state with the other of the non-imaging sensor system detection state and the imaging sensor system detection state. A flame or gas detecting system detection state is then indicated at a user interface including the validated one of the non-imaging sensor system detection state and the imaging system detection state. Flame or gas detection systems and computer program products are also described.