A system includes multiple devices configured to emit and detect germicidal radiation. Each of the multiple devices operates in emitting mode when connected to a drive source in a forward bias configuration and operates in detecting mode when disconnected from the drive source or when connected to the drive source in a reverse bias configuration. Cycling circuitry generates a sequence of control signals that control switching circuitry to change the connections of the devices to the drive source in a cycle in which one or more of the multiple devices are switched to detecting mode and senses radiation emitted by one or more of the multiple devices simultaneously operating in emitting mode. Each device operating in detecting mode generates a signal in response to the sensed radiation. Detection circuitry detects signals of the devices operating in detecting mode and generates a detection output in response to the detected signals.

A wireless access device is configured to be electrically connected to a lighting device that communicates with a server. The wireless access device includes a connecting base. The connecting base includes an electrical connection interface, which is configured to be directly and electrically connected to the lighting device and to receive electric power from the lighting device. The wireless access device is configured to communicate with the server through the electrical connection interface and to receive the electric power from the lighting device through the electrical connection interface.

A system for monitoring ultraviolet (UV) exposure of a wearer. The system comprises a wearable device operable to sense UV radiation levels to which the wearer is exposed, and to transmit UV radiation information. The system further comprises an external computing device in remote communication with the wearable device, operable to receive the UV radiation information from the wearable device and configured to determine the wearer's real-time UV index value and the wearer's daily cumulative percentage of minimal erythema dose based upon the UV radiation information.

Methods and systems for determining one or more characteristics of light in an optical system are provided. One system includes a detector positioned in a path of light between a light source in the optical system and a specimen for which the optical system performs a process. The detector includes a center cut-out configured to allow only a first portion of the light from the light source to pass therethrough and four or more detector segments positioned around the center cut-out and in a path of only a second portion of the light from the light source. The four or more detector segments are configured to separately generate output responsive to the light incident thereon. The system also includes a control subsystem configured for determining one or more characteristics of the light from the light source based on the output separately generated by the four or more detector segments.

Various embodiments include a light source module with one or more light emitters and one or more light sensors that share an aperture via which light passes. One of the light sensors may measure illuminance received through the aperture (not illuminance from the light emitters) and send a signal indicating a measurement of the illuminance. The light source module may be integrated into a portable computing device having a controller. The controller may include logic to perform one or more device operations based on the measurement of illuminance, such as, but not limited to, controlling a device display brightness and/or controlling an auto exposure feature of the device camera. Calibration parameters for interpreting the signal may be determined via a calibration process.

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 an solar radiation value from the radiation sensor at a first time; and, based on the solar radiation value and the skin exposure, estimate an solar radiation exposure of the user at the first time.

Computing devices and methods for controlling light output of a display are disclosed. In one example, a default brightness setting is set to an indoor light output level. A UV light sensor is activated to detect UV radiation levels. Based on determining that one or more of the UV radiation levels exceed a UV threshold, the default brightness setting is updated to correspond to an outdoor light output level that is greater than the indoor light output level. Without using information from an ambient light sensor, the display is activated from a deactivated state to illuminate at the updated default brightness setting corresponding to the outdoor light output level.

Eyewear having radiation monitoring capability is disclosed. Radiation, such as ultraviolet (UV) radiation, infrared (IR) radiation or light, can be measured by a detector. The measured radiation can then be used in providing radiation-related information to a user of the eyewear. Advantageously, the user of the eyewear is able to easily monitor their exposure to radiation.

An extreme ultraviolet light generating apparatus moves a generation position of extreme ultraviolet light based on an instruction from an external device and includes a chamber in which a target fed therein is irradiated with laser light so that the extreme ultraviolet light is generated from the target; a target feeder configured to output and feed the target into the chamber; a condensing mirror configured to condense the laser light on the target fed into the chamber; a stage configured to regulate a position of the target feeder; a manipulator configured to regulate a position of the condensing mirror; and a control unit configured to be able to control at least one of the stage, the manipulator, and a radiation timing of the laser light to the target, in a feedforward method, when the generation position is moved during generation of the extreme ultraviolet light.

A printer includes an ultraviolet (UV) curing device having UV light emitting diodes (LEDs) to cure UV curable inks ejected onto a surface after the surface travels past a plurality of printheads in the printer. A UV detector having UV sensors is positioned opposite the UV curing device so the UV sensors and UV LEDs are opposite one another in a one-to-one correspondence. A controller operates the UV curing device to direct UV light into the UV detector and receives electrical signals generated by the UV sensors. The controller compares these electrical signals to a predetermined threshold to identify defective LEDs in the UV curing device. The controller then determines how to move the UV curing device across the path of the surface to irradiate areas of the surface previously opposite the defective UV LEDs.