128 results about "Half field" patented technology

A method, apparatus, and computer-readable media comprising generating a positioning signal comprising a first half-field and a second half-field; and transmitting the positioning signal; wherein each of the first and second half-fields comprises 313 segments; and wherein each of the segments comprises 832 chips comprising an American Television Standards Committee (ATSC) digital television (DTV) segment synchronization signal and a pseudonoise sequence.

The invention discloses an optical imaging lens. The optical imaging lens comprises a first lens with focal power, a second lens with focal power, a third lens with focal power, a fourth lens with focal power, a fifth lens with focal power, a sixth lens with focal power, a seventh lens with focal power and an eighth lens with focal power from the object side to the image side along an optical axisin sequence. The object side face of the first lens is a convex face, and the image side face of the first lens is a concave face. The object side face of the second lens is a convex face, and the image side face of the second lens is a concave face. The object side face of the eighth lens is a concave face. The maximum half-field angle Semi-FOV of the optical imaging lens and the effective focallength f8 of the eighth lens meet the formula: 2.4 millimeters<=tan(Semi-FOV)*|f8|<3.5 millimeters.

The present invention discloses an optical imaging lens. The optical imaging lens includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens which are sequentially distributed along an optical axis from an object side to an image side; the first lens has positive focal power, the object side surface and image side surface of the first lens are convex surfaces; the second lens has negative focal power; the third lens has negative focal power, and the image side surface of the third lens is a concave surface; and the fourth lens has focal power; the fifth lens has focal power, and the image side surface of the fifth lens is a convex surface; and the sixth lens has focal power, and the object side surface of the sixth lens is a concave surface. The maximum half field of view (HFOV) of the optical imaging lens is smaller than 30 degrees.

The invention provides a wide-angle lens. Manufacturing simplicity is ensured and improvement of optical properties is achieved through a low component number. The wide-angle lens comprises a negative lens group with one or two positive lenses, a positive glass lens and a positive connection lens formed by a positive resin lens and a negative resin lens through connection from an object side in order. The wide-angle lens is a wide-angle lens with a half field angle of more than 30 degrees. The connection surface of the connection lens is designed to be an aspheric surface with a decreasing sagging amount from the optical axis to the rim when the surface is compared with a paraxial spherical surface defined by paraxial curvature radius of the connection surface.

A single focus wide-angle lens includes, in order from the object side: a first lens component of positive refractive power, having a meniscus shape, and having a convex object-side surface; a stop; a second lens component of positive refractive power, having a meniscus shape, having at least one aspheric surface, having a concave object-side surface, and being made of plastic; and a third lens component of negative refractive power, having a meniscus or plano-concave or biconcave shape, having both surfaces of aspheric shape, having an image-side surface that is concave on the optical axis, and being made of plastic. The single focus wide-angle lens may include only three lens elements. Specified on-axis conditions are satisfied in order to reduce aberrations and to make the single focus wide-angle lens compact. Additionally, satisfying a condition related to the half-field angle at the maximum image height helps reduce aberrations.

The invention provides an eyepiece. The eyepiece is successively provided with a first lens with positive focal power and a convex object side and a second lens along the optical axis from the object side to the image side. The second lens has a concave image side. At least one of the object side of the first lens, the image side of the first lens, the object side of the second lens and the image side of the second lens is a Fresnel structure plane. The maximum half field angle HFOV of the eyepiece is greater than 40 degrees. According to the on-axis distance TTL from the object side of the first lens to an imaging face and the total effective focal length f of the eyepiece, 1<TTL/f<1.5. According to the total effective focal length f of the eyepiece and the on-axis distance TD from the object side of the first lens to the image side of the second lens, 2<f/TD<5. According to the effective radius DT11 of the object side of the first lens and the effective radius DT21 of the object side of the second lens, 2.7<DT11/DT21<1.

The invention discloses an optical imaging lens which sequentially comprises a first lens having positive focal power, a second lens having focal power, a third lens having focal power, a fourth lenshaving focal power, a fifth lens having focal power, a sixth lens having focal power, and a seventh lens having negative focal power from the object side to the image side along the optical axis, andthe image side surface of the fifth lens is a concave surface; the effective focal length f of the optical imaging lens and the maximum half-field angle HFOV of the optical imaging lens satisfy 5.5 mm< tan (HFOV) * f < 6.5 mm. The optical imaging lens has at least one beneficial effect of large image surface, large wide angle, large aperture, ultrathin property and the like.

There is provided a wide angle lens system configured to obtain excellent image forming performance even in a half field angle region of 40 degrees to 50 degrees. A wide angle lens system is constituted of a first lens having a negative refractive power, a light path bending member having no refractive power, a second lens having a positive refractive power, an aperture which adjusts a light amount, a first cemented lens formed by cementing a third lens having a positive refractive power and a fourth lens having a negative refractive power, a fifth lens having a positive refractive power, and an optically equivalent member which functions as a faceplate of an optical low-pass filter and a solid state imaging element.

The invention discloses an optical imaging lens. The optical imaging lens sequentially comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lensfrom an object side to an image side along the optical axis, wherein the first lens and the second lens respectively have positive focal power; the third lens, the fourth lens, the sixth lens and theseventh lens respectively have positive focal power or negative focal power; the fifth lens has negative focal power, and the surface of the fifth lens at the image side is a concave surface; the surface of the sixth lens at the object side is a convex surface; the adjacent lenses are spaced by air; the maximum angle of HFOV (half field of vision) of the optical imaging lens is smaller than 30 degrees.

The invention discloses an optical imaging lens. The optical imaging lens comprises a first lens with positive focal power, a second lens with focal power, a third lens with focal power, a fourth lenswith focal power, a fifth lens with positive focal power and a sixth lens with negative focal power from the object side to the image side along an optical axis in sequence. The object side face of the first lens is a convex face. The object side face of the fourth lens is a convex face, and the image side face of the fourth lens is a concave face. The object side face of the sixth lens is a convex face. The distance TTL, between the object side face of the first lens of the optical imaging lens and the imaging face of the optical imaging lens, on the optical axis and a half of diagonal length ImgH of an effective pixel area on the imaging face meet the formula: TTL/ImgH<1.6; the total effective focal length f of the optical imaging lens and the maximum half-field angle Semi-FOV of the optical imaging lens meet the formula: 4.5 millimeters<f*tan(Semi-FOV)<7 millimeters.

The invention provides fast building earthquake-resisting reinforcing method and device. The fast building earthquake-resisting reinforcing device is a prefabricated part, the inner side of the prefabricated part is provided with a grout groove, and the grout groove is communicated with the outer side of the prefabricated part through more than one grout hole. The reinforcing method comprises the following steps of: removing the skin of the junction surface at the junction part between a wall of the reinforced building and the prefabricated part, and drilling anchoring holes in the wall, wherein the position of each anchoring hole is corresponding to the junction hole in the prefabricated part; installing the prefabricated part on the wall of the reinforced building through anchoring bolts, anchoring adjacent prefabricated parts, and fixedly bonding the prefabricated parts to the surface of the wall together. The technical scheme of field assembly of the prefabricated parts is adopted to reinforce the building, more than half field construction period can be shortened, the prefabricated parts can be produced in factories during school time, and enough time for ensuring production quality is guaranteed.

The invention discloses a camera lens group which sequentially comprises a first lens, a second lens, a third lens and a fourth lens along the optical axis from an object side to an image side. The first lens has positive focal power, and an object-side surface of the first lens is a convex surface; the second lens has positive focal power; the third lens has positive focal power, an object-side surface of the third lens is a concave surface, and an image-side surface of the third lens is a convex surface; the fourth lens has negative focal power. The maximum half-field-of-view angle HFOV of the camera lens group meets a conditional expression of 45 <HFOV<50 .

The invention discloses a high-precision dynamic imaging simulator for a space target. The high-precision dynamic imaging simulator comprises two half-field display systems, an optical splicing system and a projection imaging system, wherein each of the half-field display systems comprises a display content generation system, a display driving system, a backlight illumination system, liquid crystal light valves and a liquid crystal light valve control system; the optical splicing system comprises a splicing lens group, a prism supporting structure and a mirror supporting structure flange; the projection imaging system comprises an object space telecentric projection lens, a lens mounting flange, a lens group fixing flange, a distance adjusting barrel and a locking device; the high-precision design of a large field of view is completed by the object space telecentric projection lens through matching of a small aperture and a short exit pupil distance, two liquid crystal light valves are fixedly arranged on splicing surfaces of the splicing lens groups, and through layout of effective display surfaces of the two liquid crystal light valves, the two liquid crystal light valves are spliced to a full field of view through the splicing lens groups; and the backlight illumination system and the liquid crystal light valves are integrally designed. According to the invention, the high-precision dynamic target simulation can be realized at a variable distance.

A single focus wide-angle lens includes, in order from the object side: a first lens component of positive refractive power, having a meniscus shape, and having a convex object-side surface; a stop; a second lens component of positive refractive power, having a meniscus shape, having at least one aspheric surface, having a concave object-side surface, and being made of plastic; and a third lens component of negative refractive power, having a meniscus shape, having both surfaces of aspheric shape, having an image-side surface that is concave on the optical axis, and being made of plastic. The single focus wide-angle lens may include only three lens elements. Specified on-axis conditions are satisfied in order to reduce aberrations and to make the single focus wide-angle lens compact. Additionally, satisfying a condition related to the half-field angle at the maximum image height helps reduce aberrations.

A wide-angle lens system having a long back focal length, disposed in front of a ⅓″ CCD camera and the focal length (f) for all lens groups is 3.0 mm, the F-number is 3.0 and the half-field angle is 46°. The following conditions are met by the first lens group: 1≦d/d3<1.2; R3/R2=0.99; and d2/f=0.03. Here, (d) indicates the thickness of the second lens along the normal line at a given distance from the optical axis within the maximum effective diameter of the object side convex surface of the lens. d3 is the thickness of the second lens along the optical axis.

The application relates to an imaging lens. The imaging lens has a maximum half field angle HFOV and a total effective focal length f, the imaging lens comprises a first lens and a plurality of subsequent lenses arranged in sequence from the object side to the image side along the optical axis, the first lens has a positive focal power, the object side surface of the first lens is a convex surface, the maximum half field angle HFOV is less than or equal to 20 degrees, and the relation between the effective focal length f1 of the first lens and the total effective focal length f satisfies the following formula: 0.5<=f1/f<=1.5.

The invention provides a design method of a star sensor lens hood and a star sensor. The design method comprises the following steps: determining a ground gas light suppression angle of the star sensor, imaging parallel lights of different incident angles which are larger than a half-field angle of a lens by a star sensor lens, analyzing an imaging gray value to obtain a lens stray light suppression angle of the star sensor lens, obtaining the half-field angle of the lens hood based on an actual image detector parameter, the lens stray light suppression angle and the ground gas light suppression angle, and obtaining the length and a clear aperture of a light-receiving end of the lens hood based on the clear aperture of the star sensor lens, the half-field angle of the lens hood and the ground gas light suppression angle. By adopting the design method provided by the invention, the problem that star point extraction is affected by the highlight of partial imaging area of a star sensor image detector due to the unreasonable design of the lens hood is effectively solved, and a sufficient basis is provided for the field angle design of the star sensor lens hood.

The purpose of the present invention is to sufficiently correct chromatic aberration of magnification through a common optical element in the later stage while aligning the direction of an image of all fields of view. A wide angle optical system (3) comprises a first group (6) having negative and positive lenses (4, 5) with negative refractive power, a second group (7) having a reflective-refractive optical element (14), and a third group (8). The reflective-refractive optical element (14) includes a first surface (11) on the object side, having a first transmitting surface (11a) and a first reflecting surface (11b) disposed surrounding the first transmitting surface, a second surface (12) on the image side, having a second transmitting surface (12a) and a second reflecting surface (12b) disposed surrounding the second transmitting surface, and a third surface (13) that is a conical transmitting surface disposed between the first surface (11) and the second surface (12) and having an apex angle toward the object. The wide angle optical system (3) satisfies the following expression: vn > vp alpha/2 > 90 DEG - theta k Where vn represents the Abbe number of the negative lens (4), vp represents the Abbe number of the positive lens (5), alpha represents the angle of the apex angle on the third surface (13), and theta k represents a half field angle (0 < theta k < 90 DEG) of principal ray in the minimum angle of view within the lateral field of view.