180 results about "Half angle" patented technology

A semiconductor laser device have, on a substrate, a semiconductor layer including an active layer sandwiched between an n-type layer and a p-type layer, the semiconductor layer having a sonator face formed by etching and a projection projecting out in an emission direction relatively to the resonator face, wherein a protective film is formed to extend from the resonator face to an end face of the projection, and, an emission critical angle, which is the largest angle at which light emitted from the resonator face can be radiated without being blocked by the projection and the protective film formed on the projection, is larger than an emission half-angle of an emission distribution in a vertical direction of a laser beam emitted from the resonator face.

An objective lens for endoscopes has a front lens unit and a rear lens unit with an aperture stop between them. The front lens unit includes a first lens element with negative refracting power of a meniscus shape, with a convex surface facing the object side and a second lens element with positive refracting power, and the rear lens unit includes a third lens element with positive refracting power, with a surface of the minor radius of curvature facing the image side and a cemented lens component of a fourth lens element with positive refracting power and a fifth lens element with negative refracting power. The objective lens satisfies the following conditions:

−2<SF<−0.9

0.94<D/(f×sin θ)<1.7

0.86<(D₁+D₂−f₁)/(2×f₃)<1.13

where SF is the shape factor of the first lens element and is a value expressed by SF=(R2+R1)/(R2−R1) when the radius of curvature of the object-side surface is denoted by R1 and the radius of curvature of the image-side surface is denoted by R2; D is a distance (an equivalent-air medium length) from the vertex of the image-side surface of the first lens element to the aperture stop; f is the combined focal length of the entire system; θ is a half angle of view; D₁ is an actually measured distance from the vertex of the object-side surface of the first lens element to the aperture stop; D₂ is a distance (an equivalent-air medium length) from the aperture stop to the image-side surface of the third lens element; f₁ is the focal length of the first lens element; and f₃ is the focal length of the third lens element.

The device comprises a device (2) for creating an essentially linear target (4) in an evacuated space where laser beams (1) are focused, the target being suitable for interacting with the focused laser beams (1) to emit a plasma emitting radiation in the extreme ultraviolet. A receiver device (3) receives the target (4) after it has interacted with the focused laser beams (1), and a collector device (110) collects the EUV radiation emitted by the target (4). The focusing elements (11) for focusing the laser beams on the target (4) are arranged in such a manner that the laser beams (1) are focused on the target (4) laterally, being situated in a common half-space relative to the target (4) and being inclined at a determined angle lying in the range about 60° to about 90° relative to a mean collection axis (6) perpendicular to the target (4). The collector device (110) is disposed symmetrically about the mean collection axis (6) in the half-space containing the laser beams (1) focused on the target (4) and inside a conical space (8) centered on the mean collection axis (6) with a vertex situated at the target (4) and a half-angle at the vertex that is less than the angle of inclination of the focused laser beams (1) relative to the mean collection axis (6). The device is suitable for use as a source for EUV radiation in lithography for fabricating integrated circuits.

In an objective lens for an endoscope, the full angle of view exceeds 120 degrees, and a most-object-side surface of the objective lens is spherical. Further, the following condition formulas (1) and (2) are satisfied:

0.7<θ8/θ10<0.8  (1); and

5<R₁/f<15  (2),

• • where θ10: half angle of view corresponding to a maximum image height;
  • θ8: half angle of view corresponding to an image height that is 80% of the maximum image height;
  • R₁: curvature radius of the most-object-side surface; and
  • f: focal length of the entire system of the objective lens.

The invention relates to a modeling method for a compound parabolic concentrator (CPC) for a linear Fresnel light condensing and heat collecting system on the basis of matlab. The modeling method comprises the following steps: 1, determining the maximum receiving half angle theta c of the CPC; 2, using an outer diameter circle of a metal inner pipe of a vacuum heat collecting tube as a base circle of an involute; 3, rotating the involute by an angle alpha by using a circle center O as the center, so that a point C on the involute, which meets the condition that t=t0, is positioned on a center shaft of the CPC and the distance between the point C and the metal inner tube of the heat collecting tube is the sum of the distance between the point and a glass outer tube of the heat collecting tube and the distance between the glass outer tube and the metal inner tube of the heat collecting tube; 4, using a point on the involute, which meets the condition (refer to the specification), as a junction point of an involute CFB and a parabola A; 5, rotating the parabola by an angle theta c around the vertex of the parabola to enable the parabola to pass through a left junction point FB and using a right junction point FA as a focus to obtain a parabolic equation; 6, carrying out simulating calculation on a relation of a convergence rate and an intercepting ratio of the CPC by utilizing a ray tracing method, and selecting the suitable intercepting ratio.

The invention provides a zoom lens capable of achieving a half angle of view over 38 degrees at the wide-angle end, a magnification ratio 6.5 to 10 or more, and a resolving power corresponding to an imaging element of 5 to 8 million pixels, with a configuration of as few as 10 to 11 pieces of lenses. The zoom lens of the invention includes a first lens group through a third lens group I to III of positive/ negative/ positive in order from the object side, or further includes a fourth lens group of positive IV. In the zoom lens, when changing magnification from a wide-angle end toward a telephoto end, a spacing between the first lens group and the second lens group increases and a spacing between the second lens group and the third lens group decreases.

The present application discloses an optical imaging lens. The optical imaging lens includes, in an order from an object side to an image side along an optical axis: a first lens having optical power;a second lens having optical power; a third lens having negative optical power; a fourth lens having optical power and whose object side is convex; a fifth lens having optical power and whose objectside is concave; a sixth lens having optical power; a seventh lens having optical power; and an eighth lens having optical power. The total effective focal length f of the optical imaging lens and themaximum half angle of view of the optical imaging lens Semi-FOV meet: fxtan(Semi-FOV)>5.5mm, and the total effective focal length f of the optical imaging lens and the effective focal length f1 of the first lens meet: 0.5<f/f1<1.5.

A single crystal diamond element having a convex surface is disclosed, the convex surface including a spherical segment for which the maximum peak to valley deviation from a perfect spherical surface is less than about 5 μm. Alternatively or in addition, the RMS deviation from a perfect spherical surface may be less than about 500 nm, or the RMS roughness less than about 30 nm. A single crystal diamond element with a radius of curvature less than about 20 mm is also disclosed. In one aspect a single crystal diamond element having a conical half-angle greater than about 10° is described. The invention also provides a method for forming a rotationally symmetrical surface on a single crystal diamond element, comprising rotating the element about a first axis, applying a laser beam to the element in a direction perpendicular to the first axis, and translating the laser beam in two dimensions in a plane perpendicular to the direction of the beam. If the two-dimensional path follows the arc of a circle a spherical surface may be formed. The invention also provides improving a spherical surface on a single crystal diamond element by pressing a rapidly rotating cup onto a slowly rotating element. The element may be a lens, in particular a solid immersion lens.

A capsule endoscope has an imaging lens system 45a that forms an image of a substantially spherical object 40 in a plane shape on the imaging surface. The imaging lens system 45a includes first to fourth lenses L1 to L4 and an aperture diaphragm S7. The surface shapes and arrangement thereof are set in consideration of a front cover 41 of the capsule endoscope and a cover glass 56 of an imaging device. Further, the imaging lens system is configured so that the following conditional expression is satisfied with respect to an arbitrary half angle of view ω:

0.7<(Y(ω+Δω)−Y(ω))/Y(Δω)

where Y(ω) denotes an image height for the half angle of view ω of the imaging lens system, and

Δω denotes an amount of minute change of the half angle of view (ω).

The invention relates to a two-stage asymmetrical composite parabolic reflector condenser in smooth transition connection, which comprises an upper-stage parabolic reflector and a lower-stage parabolic reflector, wherein the lower-stage parabolic reflector comprises axial symmetrical parabolic reflectors; the upper-stage parabolic reflector comprises asymmetrical parabolic reflectors; the profile parabola principal axes of the upper-stage parabolic reflector and the lower-stage parabolic reflector are positioned in the same axis position; the absorption end width of the upper-stage parabolic reflector and the open end width of the lower-stage parabolic reflector are equal; the upper-stage parabolic reflector and the lower-stage parabolic reflector adopt the smooth connection processing; the upper-stage parabolic reflector comprises parabolas at the left and right sides; and the received half-angle sine value ratio of the parabolas at the left and right sides is equal to the solar radiation intensity ratio of the region in spring and winter. The two-stage asymmetrical composite parabolic reflector condenser provided by the invention can effectively reduce the optical radiation energy loss, widely receive solar rays and has good season adaptability.

The invention relates to a method for fast measurement and judgment of a central line of equipment like a rotary kiln, which comprises the following steps: firstly measuring the actual horizontal projection distance A1 of the central line of a wheel belt and a support wheel, further calculating the horizontal movement adjustment quantity X of the support wheel and the support half-angle theta of the support wheel after adjustment according to a formula, judging whether the horizontal movement adjustment quantity X of the support wheel can lead the support half-angle theta of the support wheel after the adjustment to be not less than 28.5, and finally determining a group of X values which are in line with the requirements for fast adjustment of the central line of a cylinder body of the rotary kiln. The measurement method has the advantages of simpleness, easy operation, small system error, high adjustment accuracy and fast speed.

The invention discloses an LED (Light Emitting Diode) packaging device based on a graphical packaging substrate. The LED packaging device based on the graphical packaging substrate comprises a graphical substrate, at least one LED chip and a packaging adhesive body, wherein the LED chip is arranged on the graphical substrate; the packaging adhesive body covers the LED chip; the surface of the graphical substrate is provided with a projection or a recess; a line plane angle alpha between the side edge of a longitudinal cross section of the projection or the recess and the horizontal plane of the graphical substrate and the refractive index n of the packaging adhesive body satisfy the following relation: according to the invention, the light efficiency can be increased by about 35%, the light producing efficiency of the LED packaging device is largely enhanced and simple structure is also obtained; in addition, the half angle width of the LED packaging device is 45 degrees smaller than the half angle width of a traditional LED device based on a mirror face substrate; and relatively concentrated lights and convenience in secondary light distribution are obtained. Finally, because the line plane angle alpha can be freely set according to needs without need of arranging a complicated curved-plane lens, the LED packaging device based on the graphical packaging substrate is beneficial for realizing the thinning of the packaging and also favorable for being mounted downstream.

The invention relates to a compact image-formation optical system that is diminished in a diametrical direction with as few lenses as possible while well adapting to an wide-angle arrangement having a half angle of 90° or greater, and an imaging system incorporating the same. The image-formation optical system comprises, in order from its object side, a first lens L1 that is a negative lens, a second lens L2 that is a meniscus lens concave on its object side, an apertures stop S, and a lens group G having positive refracting power.