Abstract:
An optical imaging system and method for achieving a large depth of field without decreasing the relative aperture of an imaging lens. The imaging system has a light source for sequentially illuminating an object to be imaged with light of different ones of a plurality of wavelengths, and an imaging lens that has a focal length that varies with the wavelength of the light that illuminates the object. For each wavelength of light by which the object is illuminated, the imaging lens will image a different object plane onto an image receiving unit, and the image receiving unit will capture one well-focused, high resolution image of the object.
Abstract:
Devices and methods for enhancing Raman Spectroscopy are disclosed. A molecular analysis device for performing Raman spectroscopy comprises a substrate and a laser source disposed on the substrate. The laser source is configured for generating a laser radiation with a direction substantially parallel with the substrate. The molecular analysis device also includes a Raman enhancement structure, which may be disposed on the substrate or on a waveguide disposed on the substrate. The Raman enhancement structure has an active surface substantially parallel to the substrate and is configured for producing a Raman scattered radiation. The Raman scattered radiation may be produced, when the laser radiation irradiates an analyte disposed on the Raman enhancement structure, or when an evanescent field emanating from the waveguide irradiates an analyte disposed on the Raman enhancement structure. In addition, a radiation receiver disposed on the substrate is configured for receiving the Raman scattered radiation.
Abstract:
A spectroscope capable of suppressing the dimension and the cost with avoiding a problem caused by polarization dependency of the diffraction grating. The spectroscope includes a polarizing beam splitter plate 3 that divides the light from an input fiber 1 into a first and a second optical paths and polarizes each light of each optical path having different direction of polarization with each other, a Fresnel rhomb half wave plate 5 that arranges the direction of polarization of the light in the first optical path into that in the second optical path and a plane mirror 4 that deflects the second optical path such that at least a portion of an area where the light through the first optical path is incident on the diffraction grating 6 and an area where the light through the second optical path is incident on the diffraction grating overlap each other.
Abstract:
A multi-spectrum, multi-channel imaging spectrometer includes two or more input slits or other light input devices, one for each of two or more input channels. The input slits are vertically and horizontally displaced, with respect to each other. The vertical displacements cause spectra from the two channels to be vertically displaced, with respect to each other, on a single image sensor on a stationary image plane. The horizontal displacements cause incident light beams from the respective input channels to strike a convex grating at different respective incidence angles and produce separate spectra having different respective spectral ranges. A retroflective spectrometer includes a convex grating that, by diffraction, disperses wavelengths of light at different angles and orders approximately back along an incident light beam. A single concave mirror reflects both the input channel and the dispersed spectrum. A prism, set of mirrors, beam splitters or other optical element(s) folds the input channel(s) of a spectrometer to enable the input(s) to be moved away from the plane of the image sensor, thereby enabling a large camera or other device to be attached to the spectrometer without blocking the input(s). A mounting mechanism enables a curved optical element to be adjusted through lateral and transverse translations, without requiring a gimbal mount.
Abstract:
Systems, methods and devices for holographic demultiplexing of optical signals that include constituent light signals of different wavelengths. A holographic demultiplexor includes a volume hologram having holograms for redirecting the constituent light signals. A dispersion element linearly disperses the optical signal, and the individual holograms of the volume hologram spatially reflect the constituent light signals back to the dispersion member at specific angles. The volume hologram spatially reflects the constituent light signals such that they are dispersed in two dimensions. The dispersion element then reflects the two dimensionally dispersed wavelengths to a two dimensional detector array.
Abstract:
An optical filter for the selective attenuation of specific wavelengths of light includes at least one spectrally dispersive element, such as a diffraction grating or prism, in combination with an optical filter. A dispersive element separates broadband light into a constituent wavelength spread in angle space. An optical filter, or filter array, can block and/or attenuate specific wavelengths or wavelength ranges of interest while the light is angularly dispersed. A second dispersive element can recombine this filtered, separated wavelength fan of light into a coaxial broadband beam having a smoother intensity profile than the unfiltered beam.
Abstract:
A spectral measurement device comprising an entrance aperture for receiving an electromagnetic energy and a mask located at the entrance aperture in the form of a two-dimensional encodement pattern. An optical element conditions the electromagnetic energy received from the mask for presentation to the spectral dispersion element and the and a spectral dispersion element disperses the electromagnetic energy in one or more dimensions. Additionally, the optical element conditions the dispersed electromagnetic energy onto an array of detector elements.
Abstract:
An optical imaging system and method for achieving a large depth of field without decreasing the relative aperture of an imaging lens. The imaging system has a light source for sequentially illuminating an object to be imaged with light of different ones of a plurality of wavelengths, and an imaging lens that has a focal length that varies with the wavelength of the light that illuminates the object. For each wavelength of light by which the object is illuminated, the imaging lens will image a different object plane onto an image receiving unit, and the image receiving unit will capture one well-focused, high resolution image of the object.
Abstract:
A dual-channel, double-filtering, multi-pass OSA having a narrow spectral linewidth response and high ORR comprises a diffraction grating (DG), two input ports (P1′, P1″) for directing first and second input light beams (LR, LT) onto the grating; a retroreflector (RAM1) for returning the dispersed light beams to the grating for dispersion again; two intermediate output ports (P2′, P2″) for receiving the twice-dispersed light beams; two secondary input ports (P3′, P3″) coupled to the intermediate output ports by polarization-maintaining waveguides (PMF2′, PMF2″) for directing the light beams onto the grating a third time, with their SOPs having a predetermined orientation relative to the SOPs of the first and second light beams when first incident upon the grating, the retroreflector (RAM1) returning the three-times-dispersed light beams to the grating for dispersion a fourth time; and two output ports (P4′, P4″) for receiving the light beams after dispersion the fourth time.
Abstract:
A multi-spectral detector for use in a passive/active system and a method for use in identifying an object in a field of view are disclosed. The multi-spectral detection system comprises an optically dispersive element, a detector array, and an integrated circuit. The optically dispersive element is capable of separating received LADAR radiation and radiation received from a scene into a plurality of spectral components and distributing the separated spectral components; and a detector array. The detector array includes a plurality of detectors capable of detecting the LADAR radiation; and a plurality of detectors capable of detecting the spectral components of the scene radiation. The integrated circuit is capable of generating a plurality of electrical signals representative of predetermined characteristics of the detected LADAR radiation and the detected spectral components. The method comprises passively detecting scene radiation employing a detector array; and actively detecting LADAR radiation through the detector array in parallel with passively detecting the scene radiation.