A method of calibrating a driving parameter of an optical component across an operating wavelength range of the component. The method comprises placing a layer of material in a light path, the layer of material being substantially planar and substantially transparent and having a thickness of the order of wavelengths in said range and operating said component to vary said driving parameter whilst detecting light transmitted through said layer of material to obtain driving parameter versus light intensity data. The obtained data is then compared with characterizing data previously derived for said layer of material in order to calibrate said driving parameter.

An optical measurement probe for capturing a spectral response through an intervening material emitting unwanted background radiation includes: a first lens configured to receive light and collimate the light into a collimated excitation beam defining a first aperture; an objective element for focusing the collimated excitation beam to a point or region in a sample through the intervening material, wherein the objective element also receives light scattered by the sample and the intervening material and collimates the scattered light into a collimated collection beam defining a second aperture; and a blocking element within the collimated collection beam for removing the light scattered by the intervening material from the collimated collection beam received from the sample, wherein the second aperture defined by the collimated collection beam is at least two times greater than the first aperture defined by the collimated excitation beam.

A polychromator system comprising: an optical element defining an aperture; a collimation mirror for receiving light via the aperture and reflecting substantially collimated light; at least a first dispersive optical component and a second dispersive optical component, each configured to disperse the substantially collimated light received from the collimation mirror by different amounts for different wavelengths and to provide cross-dispersed light having different wavelengths of light spaced along a first and second axis; and a focus mirror positioned to focus the cross-dispersed light onto a 2-D array detector to provide a plurality of aperture images of the aperture at a respective plurality of regions of the detector, each of the plurality of aperture images associated with a respective wavelength of the cross-dispersed light. Either one or both of the collimation mirror and the focus mirror is a freeform mirror having a reflective surface configured to mitigate effects of optical aberrations of the polychromator system over a plurality of the wavelengths of the cross-dispersed light along the first axis and the second axis and thereby optimise the resolution of the plurality of aperture images associated with the plurality of the wavelengths along the first axis and the second axis.

An optical module includes a support layer, a device layer which is provided on the support layer, and a movable mirror which is mounted in the device layer. The device layer has a mounting region in which the movable mirror is mounted, and a driving region which is connected to the mounting region. A space corresponding to at least the mounting region and the driving region is formed between the support layer and the device layer. The mounting region is disposed between a pair of elastic support regions included in the driving region and is supported by the pair of elastic support regions.

A compact, catadioptric and athermal imaging spectrometer is disclosed. A telecentric light (1) incident from a slit (2) is folded or refracted by an object-side prism (3) to enter a plano-convex lens (4); after being refracted by the plano-convex lens (4) and a meniscus lens (5), and refracted and reflected by a thick catadioptric lens (6), said telecentric light is incident onto a convex grating (7) in the form of a convergent beam; and after said beam is diffracted, spectral division is implemented. The divergent beam is sequentially refracted and reflected by the thick catadioptric lens (6), and refracted by the meniscus lens (5) and the plano-convex lens (4) to enter an image-side prism (8). Said beam is folded or refracted and filtered, and imaged on a focal plane (10) to realize spectral imaging.

A compact, catadioptric and athermal imaging spectrometer is disclosed. A telecentric light (1) incident from a slit (2) is folded or refracted by an object-side prism (3) to enter a plano-convex lens (4); after being refracted by the plano-convex lens (4) and a meniscus lens (5), and refracted and reflected by a thick catadioptric lens (6), said telecentric light is incident onto a convex grating (7) in the form of a convergent beam; and after said beam is diffracted, spectral division is implemented. The divergent beam is sequentially refracted and reflected by the thick catadioptric lens (6), and refracted by the meniscus lens (5) and the plano-convex lens (4) to enter an image-side prism (8). Said beam is folded or refracted and filtered, and imaged on a focal plane (10) to realize spectral imaging.

A method for enhancement of spontaneous Raman scattering (SRS) from gases comprising a multimode blue laser diode which receives feedback from a near concentric bidirectional multipass cavity in such a way as to generate a circulating power of order 100 W for a sample volume of 10 mm.sup.3. The feedback, provided via a volume Bragg grating, reduces the laser bandwidth to 4 cm.sup.−1. Spectra of spontaneous Raman scattering from ambient atmospheric air, detected collinearly with the pump, were recorded with a limit of detection below 1 part-per-million.

A system and method are provided for spectral shaping of light from a broadband source using a linear spatial light modulator (SLM). The system includes an illumination source generating light including a plurality of wavelengths, a lens to collimate the light and an aperture to define its angular spread, a diffraction grating to disperse the beam by wavelength, and a focusing element to focus the dispersed beams from the diffraction grating onto a plurality of pixels of the SLM. The SLM is configured to individually modulate the dispersed beams by diffracting light output therefrom into higher orders, where a diffraction angle of output light is greater than an input cone angle of incoming light from the illumination source.

Object: To provide a remote substance identification device that can identify an unidentified substance, such as a harmful substance, from a remote location. Solution: Provided are a remote substance identification device and method, the device comprising a laser device 10 that emits a laser beam to an irradiated space; a wavelength conversion device 20 that converts a wavelength of the laser beam emitted from the laser device into a plurality of different wavelengths and that emits laser beams of the different wavelengths to the irradiated space; a light collecting-detecting device 30, 40, 50 that collects and detects resonance Raman-scattered light generated from an irradiated object due to resonance Raman scattering; and a processor 60 that identifies the irradiated object on the basis of a result detected by the collecting-detecting device 30, 40, 50.

A mirror unit 2 includes a mirror device 20 including a base 21 and a movable mirror 22, an optical function member 13, and a fixed mirror 16 that is disposed on a side opposite to the mirror device 20 with respect to the optical function member 13. The mirror device 20 is provided with a light passage portion 24 that constitutes a first portion of an optical path between the beam splitter unit 3 and the fixed mirror 16. The optical function member 13 is provided with a light transmitting portion 14 that constitutes a second portion of the optical path between the beam splitter unit 3 and the fixed mirror 16. A second surface 21b of the base 21 and a third surface 13a of the optical function member 13 are joined to each other.