A method of monitoring light output from at least one solid-state light source involves sensing any light produced by the at least one solid-state light source and reflected, by at least one surface spaced apart from the at least one solid-state light source, to at least one reference location spaced apart from the at least one surface. Apparatuses and uses of the apparatuses are also disclosed.

Composite material can include a matrix material, a fiber dispersed in the matrix material, and an ultraviolet (UV)-light sensitive mechanophore grafted to a surface of the fiber. A method for making a fiber-reinforced polymer composite can include contacting a fiber in a first solution, rinsing and then drying intermediate fiber, contacting dried fiber in a third solution, rinsing, and then drying the rinsed fiber thereby generating functionalized fiber that is sensitive to ultraviolet light. The functionalized fiber can be combined with a polymer matrix material, cured, and irradiated, thereby generating a fiber-reinforced polymer composite.

A method of monitoring ultraviolet radiation reflectance is provided for activating an ultraviolet radiation reflectance digital sensor and display monitor; capturing ultraviolet radiation reflectance passing through a lens onto the digital senor; analyzing ultraviolet radiation reflectance against a preloaded and predetermined color palate; generating a video image; and outputting the video image to the display monitor. A device is also provided for an ultraviolet radiation reflectance monitoring application which receives data from an ultraviolet radiation sensitive digital imaging plate installed on the device; wherein the application processes data received from the digital imaging plate and generates an output image of ultraviolet radiation reflectance to a video monitor communicatively connected to the device.

A multispectral optical sensor is disclosed. In one embodiment, the multispectral optical sensor includes a piezoelectric material, a first sensing layer and a second sensing layer spaced apart from each other on the piezoelectric material and configured to change the propagation speed of the acoustic wave propagated through the piezoelectric material by receiving ultraviolet light and visible light, respectively. The multiple optical sensor further includes a first acoustic wave output part and a second acoustic wave output part disposed on the piezoelectric material respectively corresponding to the first and second sensing layers and configured to generate an electrical signal based on the changed acoustic wave. The multiple optical sensor measures the intensity of ultraviolet and visible light using a single sensor by detecting the change in frequency, and measures the frequency change in the acoustic wave using zinc oxide, gallium nitride), or cadmium sulfide nanoparticles.

A light detection system is provided for association with a light source. The light detection system includes a light detector and circuitry. The light detector includes semiconductor film and phototube devices and is disposed with at least one line-of-sight (LOS) to the light source. The circuitry is coupled to the light detector and the light detector and the circuitry are configured to cooperatively identify a presence and a characteristic of a light emission event at the light source.

Methods, apparatuses, and systems are provided for using laser ablation to manufacture nanoparticles. An example method includes steps of generating, by a laser beam generator, a laser beam, splitting, by a set of beam splitters, the laser beam into a plurality of derivative laser beams, and directing each derivative laser beam towards a plurality of targets. In this example method, the plurality of targets are submerged in corresponding synthesis solvents within corresponding synthesis chambers. Moreover, interaction of each derivative laser beam with its corresponding target releases nanoparticles into the corresponding synthesis solvent to create a nanoparticle solution including both the corresponding synthesis solvent and the released nanoparticles.

An ultraviolet light radiation sensing device to be wearable by a human being is provided, the device including a front part and a rear part, an ultraviolet light radiation sensor with associated microprocessor on a printed circuit board, a battery, and a wireless communication unit, e.g. for Bluetooth communication. If the front and rear part are made from a metal or metal alloy, and are interconnected by a middle member made from electrically insulating polymer material, the front and rear parts constitute antenna elements of the wireless communication unit. The device is intended to enable interaction with application data of a smartphone, a method being provided to establish recommended UV-dose and related exposure time by the sun onto the skin of the human being.

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.

A wearable apparatus for indicating a threshold amount of ultra-violet (UV) light has been received by a user and method of making the same are provided. In an embodiment, a wearable apparatus includes a first material and a second material. The second material includes a color changing material that changes color from a first color to a second color when exposed to a threshold level of UV light. The wearable apparatus is configured to be worn by a user in a place exposed to sunlight. The second color indicates that the user has been exposed to a threshold amount of UV light.

The invention provides systems and methods for tissue-mounted electronics and photonics. Devices of some embodiments of the invention implement high performance, and optionally flexible, device components having miniaturized formats in device architectures that minimize adverse physical effects to tissue and/or reduce interfacial stresses when mounted on tissue surfaces. In some embodiments, the invention provides complementary tissue mounting strategies providing for mechanically robust and/or long term integration of the present devices, for example, via mounting on tissue surfaces that are not subject to rapid growth or exfoliation processes such as the fingernail, toenail, tooth or earlobe. Devices of the invention are versatile and support a broad range of applications for sensing, actuating and communication including applications for near field communication, for example, for password authentication, electronic transactions and biometric sensing.