Compact Device for Sensing a Liquid with Energy Harvesting from Liquid Motion
First Claim
1. A device for sensing a pre-determined liquid, comprising a sensing unit, the sensing unit comprising:
- a light emitting diode (LED) array for emitting light, the LED array comprising plural LEDs;
a reflector for reflecting light emitted from the LED array, the reflector including an opening for allowing a part of the emitted light to exit the reflector and form a probe light beam for sensing the liquid, the reflector being shaped to be substantially similar to one half of an ellipsoid except on the opening, the ellipsoid having a first focus and a second focus, wherein the LED array is located at the first focus so that the emitted light incident on the reflector is reflected to the second focus, causing the emitted light after reflection to be refocused at the second focus;
a first photodetector (PD) located at the second focus and used for measuring an intensity of the refocused emitted light to thereby yield a reference intensity;
a second PD for measuring an intensity of the probe light beam received after the probe light beam passes through the liquid to thereby yield a measured intensity;
a substrate on which the LED array and the first PD are mounted, wherein the reflector is located on the substrate such that an enclosed space between the reflector and the substrate is formed; and
a sealer formed by filling the enclosed space with a substantially-transparent sealing material impermeable to the liquid for sealing the LED array and the first PD from the liquid, wherein the sealer is further prepared to have a convex surface on the opening, the convex surface being shaped to refract the emitted light incident on the opening to form the probe light beam such that the probe light beam is substantially collimated when the device is immersed in the liquid.
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Accused Products
Abstract
A compact device useful for measuring an absorption spectrum of a liquid, such as water with organic contaminants, is provided. The device comprises an array of light emitting diodes (LEDs) each emitting light with a unique spectral peak. A reflector shaped as a half ellipsoid reflects the emitted light to form a reference beam. The reflector has an opening to allow part of the emitted light to form a measurement beam after passing through the liquid. Two photodetectors measure the reference beam and the measurement beam to give a reference intensity and a measured intensity, respectively. The LEDs sequentially emit showers of light one-by-one, giving plural pairs of reference and measured intensities for estimating the absorption spectrum. The device receives energy from a separate power-providing device through wireless power transfer. The power-providing device harvests motional energy of the flowing liquid to generate electrical energy.
6 Citations
20 Claims
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1. A device for sensing a pre-determined liquid, comprising a sensing unit, the sensing unit comprising:
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a light emitting diode (LED) array for emitting light, the LED array comprising plural LEDs; a reflector for reflecting light emitted from the LED array, the reflector including an opening for allowing a part of the emitted light to exit the reflector and form a probe light beam for sensing the liquid, the reflector being shaped to be substantially similar to one half of an ellipsoid except on the opening, the ellipsoid having a first focus and a second focus, wherein the LED array is located at the first focus so that the emitted light incident on the reflector is reflected to the second focus, causing the emitted light after reflection to be refocused at the second focus; a first photodetector (PD) located at the second focus and used for measuring an intensity of the refocused emitted light to thereby yield a reference intensity; a second PD for measuring an intensity of the probe light beam received after the probe light beam passes through the liquid to thereby yield a measured intensity; a substrate on which the LED array and the first PD are mounted, wherein the reflector is located on the substrate such that an enclosed space between the reflector and the substrate is formed; and a sealer formed by filling the enclosed space with a substantially-transparent sealing material impermeable to the liquid for sealing the LED array and the first PD from the liquid, wherein the sealer is further prepared to have a convex surface on the opening, the convex surface being shaped to refract the emitted light incident on the opening to form the probe light beam such that the probe light beam is substantially collimated when the device is immersed in the liquid. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
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Specification