Disclosed is a fingerprint input device using a portable terminal equipped with a camera, and an external optical device for inputting a fingerprint. According to the present invention, a fingerprint image may be generated by an optical fingerprint input method by using the external optical device of the present invention even when an existing portable terminal does not have a configuration for an optical fingerprint input. To this end, the external optical device is provided as an external type to be mounted in the existing portable terminal provided with a camera, and has an optical refractor and a mirror. The external optical device may generate a user's fingerprint image by an optical fingerprint input method, in accordance with circumstances, without interrupting the main use of a camera and an LED of the existing portable terminal.

The invention relates to a scan light device for a motor vehicle, comprising at least one light source capable of emitting light rays, characterized in that it comprises a wavelength conversion element arranged to receive the light rays on a zone and to re-emit a light radiation to produce a light beam, in that the device further comprises an element for folding the light rays back to the conversion element, and scan means configured to scan the folding element with the light rays in a first direction, the scan of the light rays being performed between extreme positions of these light rays in said first direction, the folding element being configured to deflect the light rays when they are at these extreme positions to a central part of the zone of the conversion element so as to form the central part of the light beam.

A projection lens having an optical system includes: an incidence lens on which light from an electrooptic element is incident; and an emission lens that is positioned closest to a magnification side and emits an image toward a projection surface, in which an incidence optical axis of the incidence lens is shifted in a first direction orthogonal to the incidence optical axis with respect to a center of a screen of the electrooptic element, a projection angle, which is an angle of an emission optical axis of the emission lens with respect to the projection surface, is less than 90°, and assuming that an effective diameter of the emission lens is DE, and a focal length of an entire optical system including the emission lens is f, and a half angle of view of the entire optical system is ω, ω is equal to or greater than 60°, and a value of PA defined by Expression (1) is equal to or greater than 0.1 and equal to or less than 7.

PA=DE/(f×tan ω)  (1)

A lens focusing device includes a lens holding module for clamping at least one test lens to be tested, a replaceable chart display module, and a focal length shortening module. The replaceable chart display module includes a frame structure, a first chart display element detachably disposed on the frame structure, and a plurality of second chart display elements detachably disposed on the frame structure, and each second chart display element is inclined at a predetermined angle relative to the first chart display element. The focal length shortening module includes a first focal length shortening structure and a plurality of second focal length shortening structures. The first focal length shortening structure is disposed between the at least one test lens and the first chart display element, and each second focal length shortening structure is disposed between the at least one test lens and the corresponding second chart display element.

A beam scanner of a projector-based near-eye display includes a prismatic element with a reflective polarizer and a quarter-wave waveplate (QWP). The beam-folding prismatic element receives a polarized light beam from a light source and couples the beam to a tiltable reflector, e.g. a 2D tiltable MEMS reflector, for angular scanning the beam. The light beam impinging onto the tiltable reflector is separated from the light beam reflected from the tiltable reflector by polarization. The polarization-based separation is achieved by causing the light beam to propagate through the QWP before and after impinging onto the tiltable reflector. Upon double propagation of the light beam through the QWP, the beam changes its polarization to an orthogonal polarization, which enables its separation from the impinging beam. The beam scanner may receive multiple light beams from multiple light sources. A projector and a near-eye display based on such beam scanners are also disclosed.

An air quality monitoring system that enables a wide scale deployment of instruments with enough accuracy for meaningful and actionable data is provided. In one aspect, an advanced technique is used to calibrate limited-capability gaseous chemical sensors to obtain accurate measurements by cross-calibrating those sensors with reference sensors to correct sensitivities to parameters that cause errors to measurements of targeted gases. In another aspect, air quality measurements are used to identify sources of chemicals in a localized level by accounting for local conditions using data such as ambient condition data and user-provided data about the local environment. In yet another aspect, a gaseous chemical sensor with an improved encasement having a cell for reflecting and lengthening light path is provided to reduce the limitations and enhance the accuracy of a conventional spectrophotometric gaseous chemical sensor.

A cloaking device comprises an object-side, an image-side, a cloaked region between the object-side and the image-side. An object-side optical component and an object-side tilt correction (TC) component are positioned on the object-side, and an image-side optical component and an image-side TC component are positioned on the image-side. The cloaking device is tilted relative to an object positioned on the object-side such that light from the object is incident on the cloaking device at an acute angle. The object-side TC component redirects light from the object incident on the cloaking device such that the light propagates through the cloaking device generally normal to the object-side and image-side optical components. The image-side TC component redirects light propagating through the cloaking device back to normal to the object to form an image of the object on the image-side of the cloaking device which, if not for the TC components, would be distorted.

In some implementations, an optical device may include an aperture, one or more optical elements, an optical filter, and an optical sensor. The aperture may be configured to receive light. The one or more optical elements may be configured to diffuse the light received by the aperture, direct the diffused light to the optical filter via a folded optical path, wherein a length of the folded optical path is greater than a distance between the aperture and an input surface of the optical filter, and cause the diffused light to be distributed across the input surface of the optical filter. The optical filter may be configured to filter the diffused light distributed across the input surface of the optical filter to pass portions of the diffused light associated with one or more wavelengths to the optical sensor.

Configurable afocal optical systems that can be configured to have different magnifications, including unity magnification, and which are capable of being cascaded to produce any number of magnifications.

In an illustrative configuration, a method for monitoring air quality is disclosed. The method includes accepting analyte gas into a cell and reflecting light rays into the analyte gas repeatedly across the cell into at least one sensor. The light scattered by particulate matter in the analyte gas and amount of spectra-absorption due to presence of a gaseous chemical is then measured. Based on the determined amount of spectra-absorption and the measured scattered light the gaseous chemical is then measured.