# Optical system of thermal imaging device

FIELD: physics.

SUBSTANCE: optical system consists of the input object lens sequentially arranged along the optical axis, forming an intermediate image and including the first positive, the second negative and the third positive convex-concave lenses of the projection object lens comprising the first bi-convex, the second negative concavo-convex and the third positive convexo-concave lens, and the photodetector with a cooled diaphragm.

EFFECT: improving the quality of the system image in the entire view field maintaining the size and reducing weight.

2 dwg, 2 tbl

**Same patents:**

FIELD: physics.

SUBSTANCE: system comprises an input lens, a projection lens, a compensation element and a defocusing element. The input lens constructs an intermediate real image and is in the form of a positive meniscus whose convex side faces the object space, a negative meniscus whose convex side faces the object space. The projection lens comprises a negative meniscus whose convex side faces the object space, a biconvex lens and a positive meniscus whose convex side faces the object space. The compensation element is placed between the input lens and the plane of the intermediate real image such that it can move along the optical axis, the compensation element being a positive meniscus whose convex side faces the object space. The defocusing element is in the form of plane-parallel plate and is installed such that it can enter and exit the space between the compensation element and the plane of the intermediate real image.

EFFECT: fewer optical components, compensation for thermo-optical and thermo-baric aberrations without changing the length of the optical system while maintaining image quality by changing the shape of the lenses and optimising aberrations.

3 dwg, 1 tbl

FIELD: physics.

SUBSTANCE: lens according to both versions comprises four components, the second and fourth of which are fixed and have two fixed positions each. The first component is in the form of a positive meniscus whose concave surface faces the image plane, the third component is in the form of a positive meniscus whose convex surface faces the image plane, and the fourth component is positive and is in the form of two menisci whose convex surfaces face each other. In the first version, the second component includes a biconcave lens and a negative meniscus facing the biconcave lens with its convex surface. In the second version, the second component is in the form of two negative menisci facing each other with their concave surfaces. Relationships given in the claim are satisfied.

EFFECT: wider angular field, high aperture ratio in narrow field of view mode, providing quasi-equal aperture ratio values when changing the field of view, short relative length of the lens while providing high image quality.

5 cl, 12 dwg, 2 tbl

FIELD: physics.

SUBSTANCE: microlens comprises four series-arranged components. The first component is in form of a single biconvex lens. The second component is divergent and consists of a biconcave lens and a divergent meniscus whose concave side faces the image space. The third component is divergent and consists of a biconcave lens and a converging meniscus, whose concave side faces the image space. The fourth component is in form of a single meniscus whose concave side faces the image space and a lens consisting of a biconvex lens and a meniscus whose concave side faces the object space. A biconvex lens is further placed between the first and third components.

EFFECT: high image contrast on the entire field of vision owing to plane-chromatic correction and a larger field of vision.

1 dwg, 1 tbl, 1 app

FIELD: physics.

SUBSTANCE: objective lens has two components separated by an aperture diaphragm. The first component consists of a positive meniscus whose concave side faces the image space, and a glued meniscus whose concave side faces the image space, between which there is a negative meniscus whose concave side faces the image space. The glued meniscus whose concave side faces the image space is positive and consists of a biconvex and a biconcave lens. The second component comprises a biconcave lens and two biconvex lenses. The biconcave lens and the first biconvex lens are glued. A negative meniscus whose concave side faces the object space is further placed behind the second biconvex lens.

EFFECT: larger angular and linear field of view and obtaining diffraction image quality at the centre and on the field of view.

2 cl, 1 dwg, 1 app

FIELD: physics.

SUBSTANCE: first component I with optical power φ_{I} is in form of a frontal meniscus whose concave surface faces the object space, and a biconvex lens. The second component II with optical power φ_{II} consists of a biconvex lens and a biconcave lens glued together, a biconvex lens with optical power φ_{II5} and a glued lens with optical power φ_{II6.7}, consisting of a diverging meniscus whose concave surface faces the image space, and a biconvex lens. The third component III with optical power φ_{III} is in form of a meniscus whose concave surface faces the object space, glued from a converging meniscus and a diverging meniscus. The ratio of optical power values of the lenses φ_{II5,6,7} and the lens overall φ_{l} satisfies the condition: _{II5} and the biconvex lens of the glued lens of the second component are made of material with dispersion coefficient 58<v_{d}<95.2. The diverging meniscus of the glued lens of the second component is made of material with dispersion coefficient 57<V_{d}<60.

EFFECT: improved mono and chromatic aberrations of axial and off-axis beams and a larger entrance aperture.

2 cl, 1 dwg, 1 app

FIELD: physics.

SUBSTANCE: lens consists of a fixed component having a first positive convex-concave lens, a second convex-concave lens and a third negative convex-concave lens, and a movable component having a first lens, a second convex-concave lens and an additional third positive convex-concave lens. The focal distance is changed by moving the fixed component between the second and third lenses of the fixed component into and out of the optical channel. In the fixed component, the second lens is positive and in the movable component, the first lens is convex-concave and negative, and the second lens is positive.

EFFECT: high energy capacity of the lens.

7 cl, 1 dwg

FIELD: physics.

SUBSTANCE: lens has series-arranged first group of lenses, an aperture diaphragm and a second group of lenses. The first group of lenses has two positive menisci glued together and facing the object with their convex side. The first lens of the second group is negative, faces the object with its concave side and is glued from two menisci, the second of which is positive. The second lens of the second group is positive and its convex side faces the image. The third lens of the second group is biconcave and is glued from a biconcave lens and a positive meniscus. Between the second and third lenses of the second group there is a biconvex lens and a positive meniscus whose concave side faces the image. All radii of the lenses are spherical and the material of the lens is optical clear glass.

EFFECT: operation of the lens with objects lying at a finite distance, high illumination on the edge of the image field, providing the value and sign of distortion which is sufficient for correcting distortion of an X-ray image converter distortion, high manufacturability.

4 dwg

FIELD: physics.

SUBSTANCE: lens has two components separated by an aperture diaphragm. The first component contains a negative meniscus lens whose convex surface faces the object space, a positive biconvex lens and a negative glued lens consisting of a biconvex and a biconcave lens. The second component consists of a glued negative meniscus lens whose concave surface faces the object space and consists of a biconcave and biconvex lens, a first and a second biconvex lens. The surfaces of the first and second positive lenses of the second component facing each other are aspherical.

EFFECT: reduced size and weight of the lens while maintaining high aperture ratio, image quality, linear field of view, as well as possibility of using said lens in both digital and film cameras.

4 cl, 1 dwg, 1 app, 1 tbl

FIELD: physics.

SUBSTANCE: lens has a plane-convex lens whose plane side faces the object, a plane-concave lens whose plane side faces the object, a single biconvex lens, a biconcave lens glued with a biconvex lens, a single biconvex lens, a single divergent-meniscus lens whose concave side faces the image. The following relationships are satisfied in the lens: 1.63<n_{1}=n_{2}<1.68; 1.73<n_{5}<2.1; 1.57<n_{6}<1.64; 1.6<n_{8}<1.675, where: n_{1} n_{2} n_{5}, n_{6}, n_{8} denote refraction indices of the material of the first and second lenses of the first component, the biconcave and biconvex lenses of the third component and the meniscus lens of the fourth component for line d, respectively. There is an aperture diaphragm in front of the biconcave lens. A plane-parallel plate or a light filter can be placed in front of the biconcave lens.

EFFECT: high aperture ratio and field angle in the object space with high image quality.

2 cl, 1 dwg, 2 tbl

**FIELD: **optics.

**SUBSTANCE:** objective lens can be applied for thermal imagery devices with smoothly altering field of vision; the objective lens contains the first consistently located fixed element in the form of a collecting convex-concave lens, the second movable element consisting of the first defocusing convex-concave lens and the second concavo-concave lens, the third movable component in the form of the convexo-convex lens and the last immovable component containing the first collective convex-concave lens and the second defocusing concave-convex lens; the focal distance f_{1} of the first component is selected in accordance with the dependency: f_{1}=(from 0,545 to 0,8)f_{t}, wherein f_{1} is the focal distance of the first component, f_{t} - the maximum focal distance of the objective lens.

**EFFECT: **demagnification of the length of the infrared objective lens regarding maximum focal distance upon the retention of sufficiently high image quality.

1 dwg, 3 tbl.

FIELD: physics, optics.

SUBSTANCE: invention relates to a laser beam focusing head for laser cutting, a method and an apparatus for laser cutting of a metal component. The focusing head comprises a collimating lens (13) and a focusing lens (14). The collimating lens (13) and the focusing lens (14) are made of ZnS and have peripheral thickness of at least 5 mm. A deflecting mirror (15) operating at an inclination angle (α) from 40° to 50° is placed between the collimating lens (13) and the focusing lens (14) on the path of the laser beam. The laser cutting apparatus comprises a solid-state laser device (SL) emitting a laser beam with wavelength of 1.06 mcm to 1.10 mcm and power of 0.1 kW to 25 kW, said focusing head and a conveying fibre (CF) connecting the solid-state laser device (SL) and the focusing head.

EFFECT: invention provides a stable focusing position of a laser beam during cutting.

13 cl, 5 dwg, 1 tbl

FIELD: physics.

SUBSTANCE: system comprises an input lens, a projection lens, a compensation element and a defocusing element. The input lens constructs an intermediate real image and is in the form of a positive meniscus whose convex side faces the object space, a negative meniscus whose convex side faces the object space. The projection lens comprises a negative meniscus whose convex side faces the object space, a biconvex lens and a positive meniscus whose convex side faces the object space. The compensation element is placed between the input lens and the plane of the intermediate real image such that it can move along the optical axis, the compensation element being a positive meniscus whose convex side faces the object space. The defocusing element is in the form of plane-parallel plate and is installed such that it can enter and exit the space between the compensation element and the plane of the intermediate real image.

EFFECT: fewer optical components, compensation for thermo-optical and thermo-baric aberrations without changing the length of the optical system while maintaining image quality by changing the shape of the lenses and optimising aberrations.

3 dwg, 1 tbl

FIELD: physics.

SUBSTANCE: infrared system consists of a first channel, comprising an afocal attachment and a focusing lens arranged in series, a second comprising an input lens and a projection lens and a photodetector which are common for the first and second channels and are arranged in series. The system also comprises devices for switching radiation flux from the first and second channel to the photodetector. In the first channel, the focusing lens has a discretely variable focal distance. In the second channel the input lens has a smoothly variable focal distance. The radiation flux switching device is installed in front of the projection lens.

EFFECT: longer detection range and high spatial resolution of the system owing to smoother variation of the focal distance by expanding the variation range of focal distance towards the maximum value.

5 cl, 1 dwg, 4 tbl

FIELD: physics.

SUBSTANCE: photodetector head comprises two groups of lenses and an aperture diaphragm in between. The first group of lenses has a negative optical power and consists of two negative convex-concave menisci and a separate positive lens. The second group of lenses has a positive optical power and consists of a separate positive lens and a double-lens glued positive component. The lenses are made of materials with good ultraviolet radiation transmission. A first group of filters is placed between the negative convex-concave meniscus and the separate positive lens, and a second group of filters is placed between the separate positive lens and the aperture diaphragm.

EFFECT: larger angular field of view and longer object detection range.

21 cl, 1 dwg

FIELD: physics.

SUBSTANCE: lens has three components. The first fixed component comprises a first positive convex-concave lens and a second biconvex lens, the second surface of which is aspherical. The second component comprises a negative lens, the first surface of which is aspherical, and is configured to move along an optical axis. The third fixed component comprises a first biconvex lens and a second positive lens. The second movable component is located between the first and second lenses of the fixed first component.

EFFECT: improved energy characteristics and angular resolution of the lens due to a larger diameter of entrance pupil and focal distance.

5 cl, 1 dwg, 3 tbl

FIELD: physics.

SUBSTANCE: lens comprises a first positive meniscus made of oxygen-free glass IKS-25, whose concave surface faces the image plane, a second negative meniscus made of zinc selenide, whose concave surface faces the image plane, a third negative and a fourth positive menisci made of germanium, whose concave surfaces face the image plane. The following relationships are satisfied: φ_{1}:φ_{2}:φ_{3}:φ_{4}=(0.72-0.85):-(1.28-1.76):-(3.00-6.00):(0.79-0.92), where φ_{1}, φ_{2}, φ_{3}, φ_{4} denote relative optical power of the first, second, third and fourth menisci, respectively.

EFFECT: high image contrast on the entire field of vision in a wide temperature range.

2 cl, 3 dwg, 3 tbl

FIELD: physics.

SUBSTANCE: lens according to both versions comprises four components, the second and fourth of which are fixed and have two fixed positions each. The first component is in the form of a positive meniscus whose concave surface faces the image plane, the third component is in the form of a positive meniscus whose convex surface faces the image plane, and the fourth component is positive and is in the form of two menisci whose convex surfaces face each other. In the first version, the second component includes a biconcave lens and a negative meniscus facing the biconcave lens with its convex surface. In the second version, the second component is in the form of two negative menisci facing each other with their concave surfaces. Relationships given in the claim are satisfied.

EFFECT: wider angular field, high aperture ratio in narrow field of view mode, providing quasi-equal aperture ratio values when changing the field of view, short relative length of the lens while providing high image quality.

5 cl, 12 dwg, 2 tbl

FIELD: physics, navigation.

SUBSTANCE: invention relates to the field of detection of infrared radiation of low altitude objects. A complex of equipment for air observation includes installation of a thermal imaging camera on a fastened balloon with the possibility of circular rotation of the camera around the vertical axis and variation of the angle of camera inclination to the vertical axis due to its placement on the horizontal shaft. Two thermal imaging cameras are placed on two fastened balloons. Cameras represent infrared mirror-lens telescopes having mosaic photodetecting devices, comprising a large number of pixels 1024×1024, read in series with the help of a CCD matrix. Balloons are filled with hydrogen produced directly in place, by means of water electrolysis.

EFFECT: invention is aimed at increased sensitivity of detection of low-altitude objects.

1 dwg

FIELD: physics.

SUBSTANCE: optical system for a thermal imaging device comprises, arranged in series on the beam path, an input lens which constructs a real intermediate image and comprises a negative and a positive meniscus, and a projection lens mounted in front of a photodetector and comprising, arranged in series on the beam path, a first meniscus, a second negative meniscus whose convex side faces the photodetector, a third positive meniscus whose convex side faces the object space, and a fourth positive meniscus whose convex side faces the photodetector. In the input lens, the negative meniscus lies first on the beam path and after the positive meniscus there is an additional negative meniscus whose convex side faces the real intermediate image. In the projection lens, the first meniscus is positive and its convex side faces the photodetector, and the fourth meniscus is located between the third meniscus of the projection lens and the photodetector.

EFFECT: high resolution of the optical system of the thermal imaging device while maintaining compactness thereof.

1 tbl, 1 dwg

FIELD: physics.

SUBSTANCE: objective lens has two components separated by an aperture diaphragm. The first component consists of a positive meniscus whose concave side faces the image space, and a glued meniscus whose concave side faces the image space, between which there is a negative meniscus whose concave side faces the image space. The glued meniscus whose concave side faces the image space is positive and consists of a biconvex and a biconcave lens. The second component comprises a biconcave lens and two biconvex lenses. The biconcave lens and the first biconvex lens are glued. A negative meniscus whose concave side faces the object space is further placed behind the second biconvex lens.

EFFECT: larger angular and linear field of view and obtaining diffraction image quality at the centre and on the field of view.

2 cl, 1 dwg, 1 app

FIELD: optics.

SUBSTANCE: device has six-lens positive and two-lens negative components, in first of which serially placed are biconvex and biconcave lenses, and second component consists of biconcave and biconvex lenses.

EFFECT: higher precision.

4 dwg