1619 results about "Partial reflection" patented technology

The present invention is directed toward a device for biometric authentication. The device comprises an infra red signal transmitter, signal receiver, memory module, and processing module. The signal transmitter transmits infrared energy toward a user. The infrared energy is partly absorbed and partly reflected by the user's body. The infra red signal receiver collects partly reflected infrared energy. The memory module stores the data, and the processing module processes and compares the reflected infrared energy and stored data for use in biometric authentication.

According to one embodiment of the present invention, an electrochromic rearview mirror assembly for a vehicle includes an electrochromic mirror having a variable reflectivity, a glare sensor for sensing levels of light directed towards the front element from the rear of the vehicle, an ambient sensor for sensing levels of ambient light, a display positioned behind the partially transmissive, partially reflective portion of the reflector for displaying information therethrough; and a control circuit coupled to the sensors and the display. The control circuit determines whether daytime or nighttime conditions are present as a function of the ambient light level sensed by the ambient sensor. During daytime conditions, the control circuit responds to light levels sensed by the glare sensor to control a contrast ratio of light originating from the display and light reflecting from the partially transmissive, partially reflective area of the reflector.

There is provided an optical device including a light-transmitting substrate having at least two major surfaces and edges, optical means for coupling light into the substrate by total internal reflection and at least one partially reflecting surface located win the substrate.

An optical measurement device and method are presented for use in non-invasive measurements on a patient's body. The device comprises an illumination assembly configured and operable to generate illuminating light of a predetermined wavelength range; a detection assembly; and a light directing assembly. The detection assembly comprises a first detector unit for detecting a first light signal transmitted through an illuminated body portion and generating first measured data indicative of the detected transmitted light, and a second detector unit for detecting a second light signal reflected from the illuminated body portion and generating second measured data indicative of the detected reflected light. The light directing assembly comprises a light diffuser for scattering back light incident thereto, to thereby direct the illuminating light or the light coming from the body portion back towards the body portion. This technique provides for increasing the amount of light reaching a region of interest inside the body portion and maximizing homogeneity of the first and second detected light signals.

There is provided an optical system, including a mechanical body (110), a light-transmitting substrate (20) having two major surfaces and edges, embedded in the mechanical body, an optical element (90) for coupling light into the substrate by total internal reflection and a plurality of partially reflecting surfaces (22) carried by the substrate, wherein the partially reflecting surfaces are parallel to each other and are not parallel to any of the edges of the substrate. The system also includes an image capturing device (112), a display source (4), and an image-processing unit (114). The image-capturing device (112) is connected via the image-processing unit (114) to the display source (4).

An eyepiece for a head mounted display includes a display module, end reflector, and viewing region. The end reflector is disposed at an opposite end of the eyepiece from the display module to reflect the display light back from a forward propagation path to a reverse propagation path. The viewing region is disposed between the display module and the end reflector and includes a partially reflective surface, that passes the display light traveling along the forward propagation path and redirects the display light traveling along the reverse propagation path out of an eye-ward side of the eyepiece along an emission path. The partially reflective surface has a compound folding angle such that the emission path of the display light emitted from the eyepiece is folded along two axes relative to the reverse propagation path between the concave end reflector and the partially reflective surface.

An eyepiece for a head mounted display includes an imaging region and a viewing region. The imaging region includes a camera. The viewing region is aligned with an eye of a user and includes a first beam splitter and a second beam splitter. The viewing region is partially transparent to pass a first portion of ambient scene light received through an ambient scene side of the eyepiece out an eye-ward side of the eyepiece. The first BS and the second BS are partially reflective and oriented to redirect offset portions of the ambient scene light received through the ambient scene side along the eyepiece towards the imaging region. The camera is positioned to capture both of the offset portions of the ambient scene light redirected by the first beam splitter and the second beam splitter.

A transflective display having a reflective viewing mode and a transmissive viewing mode is provided. The transflective display includes a liquid crystal (LC) panel having an array of partially reflective pixels. The reflective portions of the array of partially reflective pixels include metal positioned on a viewer side of the LC panel to reflect light back toward the viewer. The display also includes a reflective polarizer, in place of a conventional rear polarizer, positioned behind the LC panel on a side of the LC panel opposite the viewer side. The reflective polarizer is also oriented to reflect ambient light back toward the viewer.

An optical device, including a light waves-transmitting substrate has two major surfaces and edges, optical means for coupling light into the substrate by total internal reflection, and a plurality of partially reflecting surfaces (22a, 22b) carried by the substrate. The partially reflecting surfaces (22a, 22b) are parallel to each other and are not parallel to any of the edges of the substrate, one or more of the partially reflecting surfaces (22a, 22b) being an anisotropic surface. The optical device has dual operational modes in see-through configuration. In a first mode, light waves are projected from a display source through the substrate to an eye of a viewer. In a second mode, the display source is shut off and only an external scene is viewable through the substrate.

There is provided an optical device, having a light-transmitting substrate (20) having at least two major surfaces parallel to each other and edges; a display light source; optical means for coupling light from the light source into the substrate (20) by internal reflection, and at least one partially reflecting surface (22) located in the substrate (20) which is non-parallel to the major surfaces of the substrate wherein the source emits light waves located in a given field-of-view, that the light waves are collimated, that an angular resolution is defined for the optical device, and wherein the angular deviation between any two different rays located in one of the collimated light waves, is smaller than the angular resolution.

An apparatus and a method for acquiring an image of skin topology. The apparatus comprises at least one light source, configured to form a source beam; at least one illuminating diffractive optical element (DOE) disposed in the optical path of the source beam, configured to diffract the source beam, thereby forming an illuminating beam; a skin contact surface, disposed in the optical path of the illuminating beam, configured to at least partially reflect the illuminating beam at regions of the boundary between the skin contact surface and skin that are not in contact with skin, thereby forming a reflected beam; at least one imaging diffractive optical element (DOE), disposed in the optical path of the reflected beam, configured to diffract the reflected light beam, thereby forming an image beam; and a sensor array, configured to receive at least a portion of the image beam and thereby to detect the acquired image.

Light sources are disclosed. A disclosed light source includes a III-V based pump light source (170) that includes nitrogen and emits light at a first wavelength. The light source further includes a vertical cavity surface emitting laser (VCSEL) that converts at least a portion of the first wavelength light (174) emitted by the pump light source (170) to at least a partially coherent light at a second wavelength (176). The VCSEL includes first and second mirrors (120, 160) that form an optical cavity for light at the second wavelength. The first mirror (120) is substantially reflective at the second wavelength and includes a first multilayer stack. The second mirror (160) is substantially transmissive at the first wavelength and partially reflective and partially transmissive and the second wavelength. The second mirror includes a second multilayer stack. The VCSEL further includes a semiconductor multilayer stack (130) that is disposed between the first and second mirrors and converts at least a portion of the first wavelength light to the second wavelength light. The semiconductor multilayer stack (130) includes a quantum well that includes a Cd(Mg)ZnSe alloy.

Substrate-guided relays that employ light guiding substrates to relay images from sources to viewers in optical display systems. The substrate-guided relays are comprised of an input coupler, an intermediate substrate, and an output coupler. In some embodiments, the output coupler is formed in a separate substrate that is coupled to the intermediate substrate. The output coupler may be placed in front of or behind the intermediate substrate, and may employ two or more partially reflective surfaces to couple light from the coupler. In some embodiments, the input coupler is coupled to the intermediate substrate in a manner that the optical axis of the input coupler intersects the optical axis of the intermediate substrate at a non-perpendicular angle.

PCT No. PCT/AU95/00303 Sec. 371 Date Mar. 10, 1998 Sec. 102(e) Date Mar. 10, 1998 PCT Filed May 24, 1995 PCT Pub. No. WO96/37732 PCT Pub. Date Nov. 28, 1996An adjustable reflector device is disclosed. The device consists of an adjustable double parabolic reflective skin (1,2) with an adjustable lamp mount (12), incorporating a V-shaped perforated heat shield (17), attached. The two part reflective skin (1,2) forms a double parabolic shape when flexed back against a reinforced spine (3). This flexible shape is secured by lengthwise adjustable chain retainers (4) attached at both ends of the skin (1,2). The lamp mount (12) slides onto a pair of threaded bolts (6,7) secured to the skin and adjustment is achieved by tightening or loosening the appropriate nuts (15,16). The heat shield (17) slides onto the lamp fitting (18) and is positioned appropriately to deflect incident heat and light. This device can be used to provide variable conditions of artificial illumination.

A method for controlling a photolithography process includes providing a wafer having a first grating structure and a second grating structure overlying the first grating structure; illuminating at least a portion of the first and second grating structures with a light source; measuring light reflected from the illuminated portion of the first and second grating structures to generate a reflection profile; determining an overlay error between the first and second grating structures based on the reflection profile; and determining at least one parameter of an operating recipe for a photolithography stepper based on the determined overlay error. A processing line includes a photolithography stepper, a first metrology tool, and a controller. The photolithography stepper is adapted to process wafers in accordance with an operating recipe. The first metrology tool is adapted to receive a wafer having a first grating structure and a second grating structure overlying the first grating structure. The metrology tool includes a light source, a detector, and a data processing unit. The light source is adapted to illuminate at least a portion of the first and second grating structures. The detector is adapted to measure light reflected from the illuminated portion of the first and second grating structures to generate a reflection profile. The data processing unit is adapted to determine an overlay error between the first and second grating structures based on the reflection profile. The controller is adapted to determine at least one parameter of the operating recipe of the photolithography stepper based on the determined overlay error.

A wavelength separator is provided with a reflective color filter arranged to intersect with an optical path of light emerging from a principal surface of a light guide plate, and a recycle portion arranged at a side of the light guide plate opposite to the reflective color filter. Out of light incident on the light guide plate, light reflected by the reflective color filter is returned to the reflected color filter again by being reflected by the recycle portion via the light guide plate.