An optical system includes a first optical system, a second optical system, and a third optical system. The first optical system divides an input beam into a first light and a second light. The second optical system includes a concave reflective surface which reflects the first light. The third optical system directs at least one of the first light reflected from the second optical system and the second light from the first optical system to an output optical path of the third optical system.

A beam splitterreflects a portion of light emitted from a first image projector in a first direction while allowing another portion of the light to transmit in a second direction. A first retroreflectorretroreflects the light reflected in the first direction toward the beam splitter. A second retroreflectorretroreflects the light transmitted in the second direction toward the beam splitter. The beam splitterallows the light retroreflected by the first retroreflectorto transmit toward an imaging opticswhile reflecting the light retroreflected by the second retroreflectortoward the imaging optics.

A beam splitterreflects a portion of light emitted from a first image projector in a first direction while allowing another portion of the light to transmit in a second direction. A first retroreflectorretroreflects the light reflected in the first direction toward the beam splitter. A second retroreflectorretroreflects the light transmitted in the second direction toward the beam splitter. The beam splitterallows the light retroreflected by the first retroreflectorto transmit toward an imaging opticswhile reflecting the light retroreflected by the second retroreflectortoward the imaging optics.

An optical proximity sensor system to detect a distance to a target object is provided. The optical proximity sensor system includes a laser that generates an emitted optical beam at a linear polarization and an optical cavity system that includes an optical cavity defined by a distance between the laser and the target object. The target object reflects the emitted optical beam to generate a reflected optical beam. A partially reflective mirror diverts a portion of the emitted optical beam and/or the reflected optical beam. A photodetector receives the diverted optical beam and generates a proximity signal that has a frequency that is indicative of the distance to the target object based on the diverted portion of the at least one of the emitted optical beam and the reflected optical beam. A proximity processor calculates the distance to the target object based on the frequency of the proximity signal.

In an optical device, a base and a movable unit are constituted by a semiconductor substrate including a first semiconductor layer, an insulating layer, and a second semiconductor layer in this order from one side in a predetermined direction. The base is constituted by the first semiconductor layer, the insulating layer, and the second semiconductor layer. The movable unit includes an arrangement portion that is constituted by the second semiconductor layer. The optical function unit is disposed on a surface of the arrangement portion on the one side. The first semiconductor layer that constitutes the base is thicker than the second semiconductor layer that constitutes the base. A surface of the base on the one side is located more to the one side than the optical function unit.

The invention relates to an optical system and, in particular for characterizing a microlithography mask, comprising a light source for generating light of a wavelength of less than 30 nm, an illumination beam path leading from the light source to an object plane, an imaging beam path leading from the object plane to an image plane and a beam splitter, via which both the illumination beam path and the imaging beam path run.

A smart mirror can show live or recorded streaming video of an instructor performing a workout in a package that is attractive and unobtrusive enough to hang in a living room. The smart mirror includes a mirror surface with a fully reflecting section and a partially reflecting section. A display behind the partially reflecting section shows the video when the smart mirror is on and is almost invisible when the smart mirror is off. The smart mirror also has a speaker, a microphone, and a camera to enable a user to view the video content and interact with the instructor. The smart mirror may connect to the user's smart phone, a peripheral device (e.g., a Bluetooth speaker) to augment user experience, a biometric sensor to provide biometric data to assess user performance, and/or a network router to connect the smart mirror to a content provider, an instructor, and/or other users.

A multi channel beamsplitter system operating over a wide spectral band has high optical performance despite the fact that the incoming and/or exiting light is not collimated and its material is dispersive. This is achieved using wavefront compensators that are matched to the curvature of the wavefronts of the incoming and/or exiting light.

Disclosed is a high-stability nano-radian-order angle measuring method and device based on drift value feedback, belonging to the technical field of precision measurement and the field of optical engineering. The device consists of LED light sources, convex lenses, multi-slit diaphragms, beam splitters, deflecting mirrors, steering mirrors, a collimator objective set, linear array CCDs, a four-quadrant position detector and a plane mirror. The method includes: enabling two paths of measuring light beams to carry angle change information of a measured object, respectively forming respective images on two sensors, and calculating a pitch angle and a yaw angle of the measured object relative to an optical axis by using positions of the two images so as to achieve the detection capability on the angle change of the measured object. While a focal distance of the objective is greatly improved by using the collimator objective set, the linear array CCDs are used as sensors to improve a measuring range. Therefore, the technical advantage of nano-radian-order angle limit resolution is achieved under the condition of the same measuring range. The LED light sources, the convex lenses and the multi-slit diaphragms are used, and at the same time, drift value feedback is performed by using the four-quadrant position detector and the steering mirrors, and the system stability is improved to 10 nano-radian order, thus solving the problem of limitation of light beam drift value to limit resolution of an autocollimator. Additionally, a system device designed by the present disclosure has the technical advantages of small structure size, high measurement precision and high measurement frequency response.

Disclosed is a high-stability nano-radian-order angle measuring method and device based on drift value feedback, belonging to the technical field of precision measurement and the field of optical engineering. The device consists of LED light sources, convex lenses, multi-slit diaphragms, beam splitters, deflecting mirrors, steering mirrors, a collimator objective set, linear array CCDs, a four-quadrant position detector and a plane mirror. The method includes: enabling two paths of measuring light beams to carry angle change information of a measured object, respectively forming respective images on two sensors, and calculating a pitch angle and a yaw angle of the measured object relative to an optical axis by using positions of the two images so as to achieve the detection capability on the angle change of the measured object. While a focal distance of the objective is greatly improved by using the collimator objective set, the linear array CCDs are used as sensors to improve a measuring range. Therefore, the technical advantage of nano-radian-order angle limit resolution is achieved under the condition of the same measuring range. The LED light sources, the convex lenses and the multi-slit diaphragms are used, and at the same time, drift value feedback is performed by using the four-quadrant position detector and the steering mirrors, and the system stability is improved to 10 nano-radian order, thus solving the problem of limitation of light beam drift value to limit resolution of an autocollimator. Additionally, a system device designed by the present disclosure has the technical advantages of small structure size, high measurement precision and high measurement frequency response.