Abstract: The present invention relates to optical power-limiting devices, and more particularly, to an optical power-limiting passive (self-adaptive) device and to a method for limiting solar power transmission in devices such as windows, using scattering level changes in a novel thermotropic composition that contains salt nano or microparticles embedded in a solid transparent host layer, where temperature change induces change in the refraction index of the matrix as well as of the embedded particles, creating a scattering layer, substantially reflecting the incident light thus limiting the amount of light passing through the window, green house covers, car sun roofs, solar panel windows and protection layers on housing roofs and walls, as a function of ambient temperature.

Abstract: An energy efficient optical window has different optical properties when irradiated by solar light from front or back side of the window. The window is used to reflect most of the infrared light at summer times, leaving the interior cooler and to absorb most of the infrared light at winter times, making the interior hotter by heat transfer from the hot window pane. Mechanical reversal of the window, inside out, is used to apply the needed version for winter and summer. The window is coated with alternating thin metallic and dielectric layers that transmit most of the visible light while reflecting most of the infrared part of the spectrum when impinged by solar light on one side and transmit most of the visible light while absorbing most of the infrared part of the spectrum when impinged by solar light on the other side.

Abstract: A system for facilitating a consumer's selection of customized color-changing lenses for eyewear, or windows, captures a digital color image of at least the face of the consumer and displays that color image to the consumer on a video display while superimposing a pair of lenses over the eyes. The display simulates the color of the superimposed lenses when made of a selected photochromic or thermochromic material. The color of the superimposed lenses is changeable, in response to consumer-controlled inputs, over a range between (a) an initial color for the lenses when subjected to at least one of (i) a first predetermined temperature and (ii) a first predetermined light condition, and (b) a final color for said lenses when subjected to at least one of (i) a second predetermined temperature higher than said first predetermined temperature and (ii) a second predetermined light condition brighter than said first predetermined light condition.

Abstract: An optical power-limiting passive (self-adaptive) device and method for limiting optical power transmission in lenses and windows, using layers of different photochromic compositions that exploit the full solar ultraviolet (UV) and short visible light spectrum. While a typical single photochromic material is activated by a UV band of wavelengths, e.g. 340 to 380 nm, adding a layer of photochromic material that is activated by an additional band of wavelengths, e.g., 380 to 420 nm, allows the efficient use of a wider band of solar UV and short visible light, e.g., 340 to 420 nm, thus enhancing the photochromic response to solar light.

Abstract: An optical window-filter includes a thermochromic material and a light absorbing material that can be bonded chemically. Absorption of light by the light absorbing material generates heat that causes phase transformation of the thermochromic material. A filter for an infrared imaging system has detectors sensitive to radiation in an infrared transmission spectrum. The filter includes a thermochromic material and a light-absorbing material. Absorption of high-power radiation in the infrared transmission spectrum by the light-absorbing material generates heat that causes phase transformation of the thermochromic material to attenuate the high-power radiation while transmitting substantially unaffected low-power radiation in the infrared transmission spectrum.

Abstract: An optical limiter comprises a glass backing, a glass cover, and a layer of a phase changing material placed between said glass backing and said glass cover, the phase changing material comprising a transparent matrix having embedded particles of material that changes its optical properties due to temperature induced phase change of said material. The optical properties may change from transparent to reflective, from transparent to refractive or from transparent to scattering. The phase changing material is preferably at least one material selected from the group consisting of the elements Antimony, Bismuth, Cadmium, Lead, Tin and Indium and low-melting-point alloys of two or more of these elements. Two or more layers of phase changing materials may be used in a stack configuration, with each of the phase changing materials having a unique melting temperature.

Abstract: A dermatological laser apparatus for irradiating human tissue with optical pulses includes a laser source (2) producing an optical output, a pulse shaper (4) coupled to the laser source for converting the optical output into optical pulses having desired shapes, and an optical delivery tool (8) coupled to the pulse shaper for applying the optical pulses sequentially to a multiplicity of sites on the human tissue with consecutively irradiated sites being non-adjacent.

Abstract: A system for facilitating a consumer's selection of customized color-changing lenses for eyewear, or windows, captures a digital color image of at least the face of the consumer and displays that color image to the consumer on a video display while superimposing a pair of lenses over the eyes. The display simulates the color of the superimposed lenses when made of a selected photochromic or thermochromic material. The color of the superimposed lenses is changeable, in response to consumer-controlled inputs, over a range between (a) an initial color for the lenses when subjected to at least one of (i) a first predetermined temperature and (ii) a first predetermined light condition, and (b) a final color for said lenses when subjected to at least one of (i) a second predetermined temperature higher than said first predetermined temperature and (ii) a second predetermined light condition brighter than said first predetermined light condition.

Abstract: The present invention relates to an optical window-filter including a thermochromic material and a light absorbing material. An absorption of light by the light absorbing material generates heat that causes phase transformation of the thermochromic material. The present invention further relates to a filter for an infrared imaging system having detectors sensitive to radiation in an infrared transmission spectrum. The filter includes a thermochromic material and a light-absorbing material. An absorption of high-power radiation in the infrared transmission spectrum by the light-absorbing material generates heat that causes phase transformation of the thermochromic material to attenuate the high-power radiation while transmitting substantially unaffected low-power radiation in the infrared transmission spectrum.

Abstract: An optical limiter comprises a glass backing, a glass cover, and a layer of a phase changing material placed between said glass backing and said glass cover, the phase changing material comprising a transparent matrix having embedded particles of material that changes its optical properties due to temperature induced phase change of said material. The optical properties may change from transparent to reflective, from transparent to refractive or from transparent to scattering. The phase changing material is preferably at least one material selected from the group consisting of the elements Antimony, Bismuth, Cadmium, Lead, Tin and Indium and low-melting-point alloys of two or more of these elements. Two or more layers of phase changing materials may be used in a stack configuration, with each of the phase changing materials having a unique melting temperature.

Abstract: The present invention relates to an optical power-limiting composition for limiting optical power transmission for an entire solar UV spectrum. The composition includes photochromic dye molecules and UV fluorescent nanoparticles in a matrix material. The composition is configured to absorb wavelengths in the entire solar UV spectrum, including wavelengths of 300-340 nm, thereby enhancing photochromic responsiveness of the composition to solar light. The composition includes a first side that receives impinging light and a second side opposed to the first side.

Abstract: The present invention relates to optical power-limiting device, and more particularly, to an optical power-limiting passive device and to a method for limiting optical power transmission in lenses and windows, using absorption changes in a novel photochromic composition, having response to infrared light in addition to the conventional response to ultra violet light. This additional response is featuring the use of the novel photochromic composition in places where ultra violet and short wave visible light is absent, or obscured, e.g. using photochromic glasses behind the front window of a car.

Abstract: An energy efficient optical window has different optical properties when irradiated by solar light from front or back side of the window. The window is used to reflect most of the infrared light at summer times, leaving the interior cooler and to absorb most of the infrared light at winter times, making the interior hotter by heat transfer from the hot window pane. Mechanical reversal of the window, inside out, is used to apply the needed version for winter and summer. The window is coated with alternating thin metallic and dielectric layers that transmit most of the visible light while reflecting most of the infrared part of the spectrum when impinged by solar light on one side and transmit most of the visible light while absorbing most of the infrared part of the spectrum when impinged by solar light on the other side.

Abstract: An optical window-filter includes a thermochromic material and a light absorbing material that can be bonded chemically. Absorption of light by the light absorbing material generates heat that causes phase transformation of the thermochromic material. A filter for an infrared imaging system has detectors sensitive to radiation in an infrared transmission spectrum. The filter includes a thermochromic material and a light-absorbing material. Absorption of high-power radiation in the infrared transmission spectrum by the light-absorbing material generates heat that causes phase transformation of the thermochromic material to attenuate the high-power radiation while transmitting substantially unaffected low-power radiation in the infrared transmission spectrum.

Abstract: The present invention relates to optical power-limiting device, and more particularly, to an optical power-limiting passive device and to a method for limiting optical power transmission in lenses and windows, using absorption changes in a photochromic material with a fast response, featuring under a millisecond rise time and one to five seconds return/decay time.

Abstract: The present invention relates to an optical window-filter including a thermochromic material and a light absorbing material. An absorption of light by the light absorbing material generates heat that causes phase transformation of the thermochromic material. The present invention further relates to a filter for an infrared imaging system having detectors sensitive to radiation in an infrared transmission spectrum. The filter includes a thermochromic material and a light-absorbing material. An absorption of high-power radiation in the infrared transmission spectrum by the light-absorbing material generates heat that causes phase transformation of the thermochromic material to attenuate the high-power radiation while transmitting substantially unaffected low-power radiation in the infrared transmission spectrum.

Abstract: An optical power limiter comprises an input optical transmission element, an output optical transmission element, and a power-limiting element disposed between the input and output elements for transmitting optical signals from the input element to the output element. The power-limiting element comprises an optical-limiting solid mixture containing particles of at least one material that produces reversible thermal changes in response to light above a predetermined optical power level, thereby changing the optical transmission properties of the power-limiting element.

Abstract: An optical fuse or energy-switching-off device includes an optical waveguide having an input section and an output section, the two sections forming a pair of opposed surfaces extending transversely through the axes of the waveguide sections. A substantially transparent material is disposed between the opposed surfaces and comprises an electrically conductive nanotube web immersed in dielectric material, where the nanotubes are not in electrical contact with each other. The substantially transparent material forms a plasma when exposed to optical signals propagating within the optical waveguide with an optical power level above a predetermined threshold, and the plasma damages the opposed surfaces sufficiently to render the surfaces substantially opaque to light propagating within the input section of the optical waveguide so as to prevent the transmission of such light.

Abstract: An impingement angle-independent wavelength-specific limiter includes a stack of wavelength-specific limiters configured to limit impinging light having a plurality of different wavelengths. The stack includes a plurality of wavelength-specific limiters. Each one of the plurality of wavelength-specific limiters is activated by a corresponding wavelength of the impinging light and is configured to limit the corresponding wavelength of the impinging light.

Abstract: An optical fuse or energy-switching-off device includes an optical waveguide having an input section and an output section, the two sections forming a pair of opposed surfaces extending transversely through the axes of the waveguide sections. A substantially transparent material is disposed between the opposed surfaces and comprises an electrically conductive nanotube web immersed in dielectric material, where the nanotubes are not in electrical contact with each other. The substantially transparent material forms a plasma when exposed to optical signals propagating within the optical waveguide with an optical power level above a predetermined threshold, and the plasma damages the opposed surfaces sufficiently to render the surfaces substantially opaque to light propagating within the input section of the optical waveguide so as to prevent the transmission of such light.