Patent ID: 11953787
Assignee: nan
Field: Audio-visual technology (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 0:
1. An optical device suitable for imaging of an object or scene (1), said object or scene (1) emitting a writing long-wave radiation (w), said device configured to operate in a reflection mode and comprises:
A. A reading light unit (2) comprising:
(a) A light source (10) configured to generate a reading light beam and to direct said reading light beam onto a collimator (20);
(b) The collimator (20) in optical communication with said light source (10), said collimator is an optical assembly of curved mirrors or lenses designed to collimate said reading light beam, thus forming a collimated reading light beam (r), and to direct said collimated reading light beam (r) onto a resonant optically addressed spatial light modulator (ROASLM) (3);

B. A writing light unit (4) in optical communication with the ROASLM (3) and comprising an optical assembly (50) designed to receive the writing radiation (w) from the object or scene (1) and to project said writing radiation (w) onto a photosensitive layer (101) of the ROASLM (3), thereby writing an image of the object or scene (1) on said photosensitive layer (101);
C. The resonant optically-addressed spatial light modulator (ROASLM) (3) in optical communication with the reading light unit (2) and with the writing light unit (4), said ROASLM (3) is configured to receive the polarised collimated reading light beam (p-r) from the reading light unit (2) and the writing radiation (w) from the writing light unit (4), and to modulate said reading light beam (p-r) with said writing radiation (w), thus converting long-wave images of said object (1) into visible-range images or finding colour changes or spectral content of said writing radiation (w), said ROASLM (3) comprises:
a) an optically-responsive resonant structure (ORRS) (100) designed to receive the writing radiation (w) from the writing light unit (4) onto the photosensitive layer (101) of said ORRS (100), thereby writing an image of the object (1) on said photosensitive layer (101), to transform light distribution created by said image into a stimulating signal suitable for modulating the reading light beam (p-r), and to direct a thereby obtained spatially intensity-modulated reading light beam (m) to a detector (40), thus creating resonance-type variations of the received spatially intensity-modulated reading light beam (m) upon the change caused by the stimulated signal;
b) a substrate (60) comprising an inner layer of a transparent conducting electrode (TCE) for applying voltage to the ORRS (100) and an outer dielectric anti-reflection coating (ARC) layer for minimising unwanted reflections; and
c) a voltage source (105) designed to provide a voltage waveform to the substrate (60) and to a conversion layer (104) of the ORRS (100) for optimising the voltage division between the photosensitive layer (101) and the conversion layer (104) upon receiving the writing radiation (w), thus maximising the contrast of the spatially intensity-modulated reading light beam (m);

D. A detector (40) in optical communication with the ROASLM (3), said detector (40) is suitable for observing, detecting, reading and/or performing acquisition of the spatially intensity-modulated reading light beam (m) received from the ROASLM (3) to create visible-range images or detect colour changes or spectral content of the writing radiation (w) of the object or scene (1) emitting said writing radiation (w), and optionally to transmit said visible-range images or said spectral content of the writing radiation (w) to an external memory or user's interface; and
E1. A polarising device (30) installed between and in optical communication with the reading light unit (2), the ROASLM (3) and the detector (40), said polarising device (30) is either:
(i) a polarising beam splitter configured to receive the incident collimated reading light beam (r) from the collimator (20) of the reading light unit (2), to split said collimated reading light beam (r) into two separate, linearly polarised, collimated beams either reflected (s-r) or transmitted (p-r) with orthogonal polarisation, and to direct the polarised collimated reading light beam (p-r) to the ROASLM (3), thereby converting phase retardation changes of said collimated reading light beam (p-r) reflected from the ROASLM (3) into intensity variations expressed in the spatially intensity-modulated reading light beam (m); or
(ii) a polariser configured to receive the incident collimated reading light beam (r) from the collimator (20) of the reading light unit (2), to generate the polarised collimated reading light beam (p-r), and to direct said polarised collimated reading light beam (p-r) to the ROASLM (3) through an analyser configured to convert the retardation or polarisation modulation of said polarised collimated reading light beam (p-r) into the spatially intensity-modulated reading light beam (m); or
(iii) a polariser designed to receive the incident collimated reading light beam (r) from the collimator (20) of the reading light unit (2), to generate the polarised collimated reading light beam (p-r), and to direct said polarised collimated reading light beam (p-r) to the ROASLM (3);

wherein said ORRS (100) comprises:
(a) The photosensitive layer (101) in optical communication with the substrate (60), said photosensitive layer (101) is deposited on a transparent substrate and is suitable for absorbing the writing radiation (w) in a form of the long-wave image of the object or scene (1) and transforming said image into the stimulating signal across the ORRS (100);
(b) Optical layers (102) adjacent to the photosensitive layer (101) and suitable for inducing resonance effect to the stimulating signal formed in the ORRS (100);
(c) Optional alignment layers (103) adjacent to the optical layers (102) and suitable for aligning liquid crystal molecules;
(d) The conversion layer (104) adjacent to the optical layers (102) or to the alignment layers (103) and suitable for converting the resonant long-wave image of the object or scene (1) into a visible-range image;
(e) the detector (40) is an RGB coloured camera or detectors array; and
(f) the spatially intensity-modulated reading light beam (m) comprises three peaks or three dips in reflection spectra, said three peaks or dips being in the red, green and blue regions of said RGB coloured camera, and the colour changes are suitable for calculation in the external memory and correlation with the temperature at each point of the object or scene (1).