178 results about "Aperture angle" patented technology

A device for determining a reproduction position of a source of sound for audio-visual reproduction of a film scene from a plurality of individual pictures with regard to a reproduction surface having a predetermined width and a projection source having a projection reference point comprises means for providing a recording position of the source of sound, a camera position during recording, and an aperture angle of the camera during recording. In addition, provision is made of means for transforming the recording position of the source of sound to a camera coordinate system, the origin of which is defined, in relation to a camera aperture, to obtain a recording position of the source of sound in the camera coordinate system. Means for calculating the reproduction position of the source of sound in relation to the projection reference point determines whether the aperture angle of the camera equals a predetermined aperture angle, and whether or not a source of sound is located within the visual range of the camera. If the current aperture angle of the camera differs from the predetermined standard aperture angle, the reproduction position of the source of sound is spaced toward a viewer, or away from the viewer, by a distance which depends on the ratio of the standard aperture angle to the current aperture angle. Hereby, automatable sound-source positioning is achieved so as to provide not only a visually realistic, but also an acoustically realistic situation in a reproduction room using wave-field synthesis methods.

The optical system for the Fresnel lens light has an ellipsoidal reflector (1), a light source (2) and a Fresnel lens (3). The distance (a) between the Fresnel lens (3) and the reflector (1) is changeable but is related to the changeable distance (b) between the light source (2) and the reflector (1) so that the aperture angle of the propagated light beam is variable but illumination intensity of the propagated light is maintained uniform. Surfaces of the at least one Fresnel lens and/or the reflector can be structured to provide more uniform illumination of a given area. The optical system is useful for lights for film, stage, studio and photography.

The invention discloses a self-adaptive cleaning device. An electromotor is used as a prime motor, power is transmitted to brush heads through rotation of the electromotor and gear engagement transmission, and therefore uniform rotation of the brush heads is achieved. A rotating main shaft is a hollow shaft, a rotating connector is communicated with a water supply hose, water current is adjusted through a water control switch on a handle according to requirements, and a hairbrush rubs a contact surface under the flushing effect of water for washing. The free change of the aperture angle of a brush plate is achieved within certain limits through a four-link mechanism of a brush head part, and therefore vessels with multiple curved surfaces or deep openings or shallow openings are washed, and then the purpose of removing dirt is achieved with the help of friction generated between the device and the surface to be cleaned. The cleaning device is provided with the two brush heads, one is the jaw type self-adaptive brush head for protruded curved surfaces and planes, and the other is the dandelion type brush head for concave curved surfaces. The self-adaptive effect is achieved by the two brush heads through the combined effect of connecting rods, a crank sliding block and a spring mechanism, the different brush heads can be replaced according to requirements in the using process, and the device is easy and flexible to operate.

A projection lens with a short focal length and high initial aperture is proposed. Such projection lenses are used, for example, in cinema projection. The projection lens is configured such that the sum of the overall length and the back focus (12) is between 2.8 times and 4.5 times the total focal length f′. The entrance pupil is at a distance of between 100 mm and 300 mm from the last lens surface (62; 150), which faces the illuminating mirror. The minimum stop number k of the projection lens is 1.7, and the projection lens is therefore also suitable for illuminating mirrors with a high aperture angle (of up to 17°).

The invention relates to a method and a device for achieving dark-field microscopy and fluorescent microscopy by using cone mirror. The method comprises the following steps of: first generating a parallel illumination light beam or a fluorescence-induced light beam; diverging the parallel illumination light beam by the cone mirror to form a hollow beam; transmitting the hollow beam to sequentially pass through a lens I and a lens II to make the divergence angle of the emergent light from the lens II larger than an aperture angle of a microscopic objective lens; and disposing a sample at the center of the hollow beam and observing the sample by the microscopic objective lens, wherein a CCD camera can be arranged in front of the microscopic objective lens. The inventive system has high transmissivity, can conveniently achieve switching between bright-field microscopy and dark-field microscopy and can simultaneously achieve dark-field microscopy and fluorescent microscopy functions, thus solving the technical problems of prior dark-field microscopy with low illumination light transmissivity and the technical problems of prior fluorescent microscopy which needs different filters for different fluorescent dyes and is incompatible to dark-field microscopy.

The invention relates to a procedure of connecting a polyphased asynchronous generator on a polyphased alternating voltage network. The connecting is carried out by means of an adjustable, electronic connecting based on thyristors or similar variable (adjustable) connecting items, the connecting degree of which is varied during a controlled connecting course, which is controlled in consideration of the wish of a "soft" connecting on the network and a limitation of the maximum amperage during the connecting course. During the whole connecting course a continuous determination of the generator phase angle phi is carried out, and on basis of this determination a continuous adjustment of thyristors-the aperture angle is carried out, thus the aimed, successive load connection of the generator on the network (soft-connecting) is obtained. Furthermore the procedure include a new method to determine the generator phase angle phi by registering the time of zero circulation on the phase voltage, and at the same time detection of the respective thyristor voltage zero circulation point at a measuring method based on measuring of the thyristor voltage. The novelty of the invention consists in adjusting the ignition point of the thyristors successively to the phase angle phi, thus the connecting degree resulted to the thyristors is increased in a controlled speed regardless of the variations registered in the phase angle during the connecting course, i.e. in the principle the thyristor aperture angle is reduced, when phi increases and so on.

A computed tomography system with an adjustable focal spot-to-detector distance has a gantry provided with a patient opening, an x-ray tube and a detector, respectively mounted at opposite sides of the gantry. The x-ray tube has a focal spot and the x-ray fan beam radiated from the focal spot exhibits a fixed aperture angle. The x-ray tube is installed on a linear track and can be moved along the rail of the linear track.

The ink-jet recording device includes an image forming section where an active energy ray-curable ink is ejected onto a recording medium to form an image, and an image curing section which includes at least one light irradiation unit having a fluorescent lamp and which cures the ink on the recording medium upon exposure to active energy rays. The fluorescent lamp has a bulb, a reflective film formed on a bulb inner wall and having a first aperture formed on a recording medium side, and a phosphor film formed on the reflective film and the bulb inner wall and having a second aperture formed on the recording medium side. The formulas: β<α, 60°≦α≦150° and 30°≦β≦90° where α represents a first aperture angle of the first aperture and β represents a second aperture angle of the second aperture are satisfied.

The invention discloses a beam combining, emitting and receiving method of lasers and a system, which belong to the technical field of photoelectricity and are used for carrying out beam combination, emission and reception on multi-beam multi-band high-power lasers. The beam combination, the emission and the reception of lasers in incidence in a plurality of directions are realized by adopting the reflection of a film at the side face of a prism, the incidence and the penetration of an end face, an optical fibre bar and a collimating mirror. The system contains a plurality of laser light sources, a multi-dimensional beam combiner, a shaper, a collimating mirror, a receiving and detecting unit and a computer system. The multi-dimensional beam combiner contains a multi-face prism and a prism holder, wherein the multi-face prism is provided with an end face and a plurality of reflecting mirror faces. A plurality of lasers are irradiated on the end face and the reflecting mirror faces of the multi-dimensional beam combiner from the periphery, the lasers of which the beams are combined are gathered on the input end face of the shaper at an aperture angle smaller than the numerical value of optical fibers, the output lasers are collimated into quasi-parallel light by the collimating mirror for irradiating a target, and the diffuse reflection lasers and the laser-induced radiation patterns of the target are received by the receiving and detecting unit positioned at the position of the focal point of the collimating mirror so as to realize the detection of the target and the acquisition of images.

The invention discloses a velocity ambiguity resolution angle measurement method for vehicle-mounted LFMCW radar, belongs to the signal processing technology, and particularly relates to the velocityambiguity resolution and radar virtual aperture direction of arrival measurement technology. According to the invention, velocity ambiguity resolution and MIMO radar virtual aperture angle measurementprocessing are carried out in one frame of signal, a two-transmitting four-receiving radar system is taken as an example, a radar transmitting end transmits linear frequency modulation continuous wave signals with different slope durations and the same bandwidth by using a time division multiplexing technology, and a radar receiving end simultaneously receives signals reflected by two transmitting antennas through an object by using four receiving antennas. Echo signals are subjected to frequency mixing, low-pass filtering and analog-to-digital conversion and finally enter a digital signal processor DSP. 2D-FFT and two-dimensional constant false alarm detection are performed in the DSP, then resolution of velocity ambiguity and phase compensation are conducted, and finally MIMO radar virtual aperture angle measurement processing is carried out, thus realizing the purpose of the invention. The method has the effects of reducing the signal processing time and improving the radar data rate.

The invention discloses a large-caliber light beam coupler, which comprises a conical optical device, a reflecting index matching solution and bare optical fiber with smoothly-cut end surfaces; the conical optical device is an optical device which is centrally symmetrical, wherein the middle part of the optical device is a conical body; an optical spherical lens is machined on the front end of the conical body, and the image focal point of the optical spherical lens is positioned at the tail end of the conical body, and the clear aperture reaches more than 1mm; a light guide pipe is arranged at the tail end of the conical body, the clear aperture of the light guide pipe is matched with the core diameter of the bare optical fiber, and the aperture angle of an outgoing light beam of the light guide pipe is compressed by connecting the light guide pipe with the optical fiber through the reflecting index matching solution in a coupling manner; and a cover layer is respectively arranged on the outer surfaces of the conical body and the light guide pipe and is used for enabling light entering the surface of the conical body to generate total reflection, and the incident light can be bounded inside the conical optical device, and the light is enabled to be transmitted forwards. The large-caliber light beam coupler disclosed by the invention is simple and compact in structure, high in coupling efficiency and capable of directly coupling the light beams with larger calibers to enter the optical fiber.

A device for determining the aperture angle of a joint includes a detection device for detecting positions of joint components and/or positions of structures connected to or to be connected to the joint and a computational unit for ascertaining the aperture angle of the joint based on the detected positions.

In order to produce a Fresnel lens spotlight whose emitted light beam has an adjustable aperture angle, having a preferably ellipsoid reflector, a lamp and at least one Fresnel lens, which has a more compact form and is thus not only more space-saving but is also lighter than the conventional Fresnel lens spotlight, a lens with a negative focal length and a virtual focal point is used as the Fresnel lens.

The invention relates to a projection objective which consists of at least seven lenses that are adjacent to air on both sides. The inventive projection objective meets the criteria of the following equations in its totality: u>=12.8°; 100 mm<=LEP<=400 mm; sigmaRBa>=1°; sigmaRBi<=-14°, whereby u is the aperture angle (2u-entire angle) on the illumination side; LEP is the distance from the entrance pupil (on the illumination side) to the object level (the position in the direction of projection from the reference point: object level corresponds to a positive value); sigmaRBa is the angle inclination of the beam in relation to the optical axis in the object space between the object and the 1. lens surface of the objective, said beam limiting the bundle for the field edge (outer field point in the object) towards the outside (away from the optical axis, far from the axis) and sigmaRBi is the angle inclination of the beam in relation to the optical axis in the object space between the object and the 1. lens surface of the objective, said beam limiting the bundle for the field edge (outer field point in the object) towards the inside (towards the optical axis, close to the axis). The angles sigmaRBa and sigmaRBi are positive when the corresponding beams intersect the optical axis in a point which is situated in the opposite direction of projection when seen from the object. Said angles are negative when the beams intersect the optical axis in a point which is situated in the direction of projection when seen from the object.

An apparatus for measuring soot content in diesel engine oil in real time comprises an optical rod capable of transmitting light and having a boundary surface adapted to be in contact with the diesel engine oil and first and second end portions, a light-emitting portion, and a first optical fiber connected to the light-emitting means. The first optical fiber is adapted to transmit light from the light-emitting means to the first end portion of the optical rod in an aperture angle of the optical fiber to the boundary surface. The apparatus also comprises a light-receiving portion adapted to receive light from the optical rod and output a signal corresponding to the received light power. The refractive index of the optical rod is larger than the refractive index of the diesel engine oil. The aperture angle of the optical fiber is equal to or larger than a critical angle reduced to air at which the light is totally reflected by the boundary surface.

The invention relates to the technical field of security check, in particular to a security check system. The provided security check system comprises a back scattering scanning device and a support device, wherein a check channel allowing a checked article to pass is formed by the support device, the back scattering scanning device is arranged at the upper part of the support device and comprisesa back scattering radiation source device and a back scattering detection device, and the support device adjusts the height of the back scattering scanning device. By means of the support device of the security check system, the height of the back scattering scanning device mounted on the support device can be adjusted, the sizes of a flying point light spot projection and the aperture angle areconveniently adjusted according to the height of the checked article in the scanning process, and therefore, the imaging quality of a back scattering image can be effectively improved.

The device for the pixel-by-pixel photoelectric measurement of a planar measured object includes projection means for the imaging of the measured object onto a two-dimensional CCD image sensor, filter means provided in the imaging light path for the wavelength selective filtering of the measuring light impinging on the image sensor, signal processing means for the processing of the electrical signals produced by the image sensor and for the conversion thereof into corresponding digital raw measured data, as well as data processing means for the processing of the raw measured data into image data representing the colors of the individual image elements of the measured object. Furthermore, illumination means are provided which include a Fresnel lens, which illuminate the measured object with at least one essentially parallel light bundle under an angle of incidence of essentially 45°+/−5°. The projection means which include at least one tele-lens constructed as a Fresnel lens, are constructed as tele-centrical imaging optics, which image each point of the measured object under essentially the same angle of observation of essentially 0° and with essentially the same aperture angle of essentially maximally 5° onto the light converter element array. The data processing means carry out extensive correction measures.

A pocket hole jig includes base with a base plate and first and second lateral side walls extending along the base plate, and a body disposed between the first and second lateral side walls and slidable along the base in a forward direction and a rearward direction. The body includes a drill bit aperture angled downward toward the base plate. The pocket hole jig also includes a fence movable between a raised position and a lowered position and having a contact surface engageable with an end of the workpiece when the fence is in the lowered position to position the base a predetermined distance from the end of the workpiece. The contact surface is in a first position when the fence is in the raised position and a second position when the fence is in the lowered position. The second position is forward of the first position.