33 results about "Symmetric systems" patented technology

Ion implantation systems and beamlines therefor are disclosed, in which a ribbon beam of a relatively large aspect ratio is mass analyzed and collimated to provide a mass analyzed ribbon beam for use in implanting one or more workpieces. The beamline system (12) comprises two similar magnets (22, 24), where the first magnet (22) mass analyzes the ribbon beam to provide an intermediate mass analyzed ion beam, and the second magnet (24) collimates the intermediate beam to provide a uniform mass analyzed ribbon beam to an end station.(18). The symmetrical system provides equidistant beam trajectories (41, 43) for ions across the elongated beam width so as to mitigate non-linearities in the beam transport through the system, such that the resultant mass analyzed beam is highly uniform.

A microscope apparatus configured to enlarge entrance pupils while maintaining the rotational symmetry of optical systems of a plurality of optical paths after ejection of light from an objective lens to bring out the performance of the objective lens. A microscope apparatus includes an objective lens having a function of collecting light from the object; and optical paths in which all lens groups are rotational symmetric systems and through which light exited from the objective lens passes, wherein when a sum of maximum diameters of entrance pupils of optical systems forming any two of the optical paths is set as ΣDi, and an axial luminous flux diameter determined from a maximum aperture angle α and a focal distance f of the objective lens is set as Dobj, a condition of the following expression is satisfied, ΣDi>Dobj where Dobj=2·f·sin α.

The invention discloses a control method for an asymmetric electric-hydraulic proportional system based on model transferring. By converting a transfer function, an asymmetric mathematical model of the asymmetric electric-hydraulic proportional system is converted into a symmetric system model, the symmetry of a load flow model is achieved, and when a unified controller is adopted, responses of forward and reverse motions are identical; by means of signal conversion, the load flow model of the asymmetric system is established, and the purposes of transfer function converting and model converting are achieved, and a new established system model serves as a symmetric load flow model. The achieving method comprises the steps that a reference signal symmetrical to a proportional valve is given, after a signal is converted, a new input signal of the proportional valve is obtained, and proportional valve is controlled to work, so that load flows of the asymmetric electric-hydraulic proportional system in a proportional valve linear region in the forward motion and the reverse motion is identical; by means of the method, an asymmetric effect is eliminated by an asymmetric factor of the system through mathematical conversion, and the identical response of the asymmetric electric-hydraulic proportional system is achieved simply and intelligently.

A unit magnification projection optical system includes, listed in order along a system axis, a mirror, a lens group having negative power and a lens group having positive power. The optical system is a symmetric system, with an object plane on one side of the system axis and an object plane on an opposite side of the system axis. The object and image planes are spaced apart from the positive lens group by a working distance greater than 100 millimeters.

The invention discloses a multi-scale multi-aperture optical imaging system. The multi-scale multi-aperture optical imaging system comprises a center optical imaging system and four secondary optical imaging systems having complete identical optical structures, wherein the center optical imaging system is a rotary symmetric system, the optical axis and the system center axis are superposed, the four secondary optical imaging systems are arranged at the back of the center optical imaging system, from the perspective of image cross sections, four optical axes of the secondary optical imaging systems are distributed on tip tops of a rectangle which takes the optical axis of the center optical imaging system as the center, and parallel lights emitted from different perspectives by a target are respectively imaged through the center optical imaging system and the four secondary optical imaging systems on different coordinate points on an image plane of one same detector. Independent multiple target images can be acquired by applying the multi-scale multi-aperture optical imaging system to acquire target object information, the center image resolution is higher than the secondary image resolution, images respectively have certain pixels superposed in the field of view, and the multi-scale multi-aperture optical imaging system can provide excellent support for subsequent data processing.

The invention discloses a symmetric control method for an asymmetric hydraulic system based on output feedback. The symmetric control method comprises the following steps that a, a state space mathematical model of the asymmetric hydraulic system is established through a load flow linearization equation of the hydraulic system, a flow equation of a working cavity of a hydraulic cylinder and a force balance equation of a valve-controlled cylinder piston; b, starting from the state space mathematical model, dynamic compensation control based on output feedback is conducted on the asymmetric hydraulic system, and thus the asymmetric hydraulic system is converted into a state space symmetric system; and c, unified PID control is conducted on the converted state space symmetric system. According to the symmetric control method, the problems of the large debugging amount and the narrow control range of an asymmetric controller of an asymmetric system for a long time are solved; control strategies are simplified, field adjustment is easier, an operator grasps system debugging more easily, and universality is better; and the reliability and the response characteristics of the system are greatly improved.