A non-dispersive multi-channel radiation sensor assembly includes a beamsplitter assembly, a first band-pass filter, which has a predefined first bandwidth and has a transmission maximum at a predefined first useful-signal wavelength, a first measurement-radiation useful-signal sensor, which is arranged downstream of the first band-pass filter in the beam path, a second band-pass filter, which has a transmission maximum at a predefined first reference-signal wavelength, a first measurement-radiation reference-signal sensor, which is arranged downstream of the second band-pass filter in the beam path. The beamsplitter assembly has a first irradiation region and a second irradiation region, in which irradiation regions the beamsplitter assembly is irradiated with measurement radiation. The irradiation regions are optically designed in such a way that the beamsplitter assembly deflects, in the first irradiation region, a first part of the measurement radiation onto the first band-pass filter and a second part of the measurement radiation onto the second band-pass filter.

A Raman spectroscopy based system and method for examination and interrogation provides a method for rapid and cost effective screening of various protein-based compounds such as bacteria, virus, drugs, and tissue abnormalities. A hand-held spectroscope includes a laser and optical train for generating a Raman-shifting sample signal, signal processing and identification algorithms for signal conditioning and target detection with combinations of ultra-high resolution micro-filters and an imaging detector array to provide specific analysis of target spectral peaks within discrete spectral bands associated with a target pathogen.

An optical assembly is disclosed including two laterally variable bandpass optical filters stacked at a fixed distance from each other, so that the upstream filter functions as a spatial filter for the downstream filter. The lateral displacement may cause a suppression of the oblique beam when transmission passbands at impinging locations of the oblique beam onto the upstream and downstream filters do not overlap. A photodetector array may be disposed downstream of the downstream filter. The optical assembly may be coupled via a variety of optical conduits or optical fibers for spectroscopic measurements of a flowing sample.

A photothermal converter using a wavelength selective perfect absorber made of a low-loss metal material or dielectric and a heat detection sensor are combined to develop a sensor that efficiently converts light of a specific wavelength into heat and further electrically detects the heat. Here, since the wavelength selective perfect absorber of the present invention has a periodic structure, it has high directivity, and can also be used as a small motion sensor or a watching sensor using detection of thermal radiation. In addition, it can also be used as a high-precision small position sensor by being combined with a laser light source matching the resonance wavelength of the sensor.

The invention relates to an optoelectronic chip comprising the following elements: a light inlet; a wavelength-sensitive optical filter; a first photoelectric element for measuring a first light intensity, particularly a first photodiode, the first photoelectric element being arranged such that light penetrating the optoelectronic chip via the light inlet, transmitted by the filter, hits the first photoelectric element; and a second photoelectric element for measuring a second light intensity, particularly a second photodiode, the second photoelectric element being arranged such that the light penetrating the optoelectronic chip via the light inlet, which is reflected by the filter, hits the second photoelectric element.

An optical spectrum analyzer (OSA) for measuring an optical spectrum of an input optical signal in a measurement wavelength range is provided. The OSA comprises a modulator, an integrated optical filter, and a photodetector. The modulator modulates the input optical signal by applying a dither modulation to facilitate detection and noise rejection. The integrated optical filter, which may include a ring resonator system, is sequentially tunable to selectively transmit each wavelength of the modulated optical signal in the measurement wavelength range. The photodetector sequentially detects each wavelength of the modulated optical signal in the measurement wavelength range to provide a representative output electrical signal.

The present invention provides a meter and method of use for measuring an optical attenuation coefficient in a liquid medium. In operation, a collimated beam, produced by a laser of the attenuation meter apparatus, propagates thru the liquid medium with filtered back-scattered light arriving at a camera of the meter. A light image is formed at a focal plane of the camera. The light image is recorded and analyzed by a microcomputer to provide optical beam attenuations coefficients.

The arrangement comprises a filter region (10) filtering electromagnetic radiation and a shielding component (20) inhibiting propagation of electromagnetic radiation. The filter region comprises a central filter region (11) and a separate peripheral filter region (13). The shielding component comprises an aperture (21). The aperture is arranged above the central filter region. The central filter region and the peripheral filter region are optimized for different angles of incidence (α, β) and provided for measurements by individual sensor regions (18, 19).

An arrangement for hyperspectral imaging, comprising an imaging sensor (170,270); a band-pass filter element (130,230): at least one imaging optics element (120,160,220,260) configured to form an image on the imaging sensor (170,270); and a first adjustable multi passband filter (150a,255); wherein the first (150a,255) adjustable multi passband filter is configured to be adjusted by tilting.

A filter for removing coherent radiation from a source in a field of view, substantially independent of the size of the source, comprises a first reticle 22 located in the path of received light 21, a first lens 23 producing an optical transform of the first reticle 22 at a second reticle 24 located in the image plane of the first lens 23, a second lens 25 producing an optical transform of the second reticle 24 and a third reticle 26 located in the image plane of the second lens 25. The arrangement is such that the spatial transmittance of the third reticle 26 is selected to block at least part of the diffracted image of the first reticle 22 produced in the image plane of the second lens 25 and characteristic of the coherent radiation. Preferably the optical transforms are Fourier Transforms. A monochromatic coherent source in the field of view produces a pattern of diffracted energy in the image plane of the second lens which is independent of the size of the source. Thus, by providing a suitable reticle 26 in the image plane of the second lens light from a coherent source in the field of view can be blocked while polychromatic light is transmitted. The first and second reticles may be periodic picket-fence reticles or different spatial frequencies may be used for the first and third reticles so as to vary the stop-band characteristics of the filter.