摘要:
A light beam scanning device of a construction, in which an image forming scanning optical system is provided with an expedient for preventing spot intensity of a light beam on a scanning surface from falling off at a peripheral region of a scanning object in comparison with its center part, and a light beam modulator is provided with an expedient for making constant a length of a single dot drawn by a beam spot with respect to one modulating signal on the scanning surface.
摘要:
A two-dimensional scanning optical system comprising a deflector capable of two-dimensional deflection of a light beam in two mutually orthogonal directions, an imaging lens system provided with a predetermined distortion characteristic and capable of focusing the light beam deflected by said deflector onto a plane to be scanned, and a light source for introducing said light beam into said deflector in a direction parallel to the optical axis of said imaging lens system, thereby achieving a scanning on said plane with substantially linear scan lines.
摘要:
Two-dimensional scanning apparatus scans a stationary two-dimensional surface with a first deflector and a second deflector which deflects a light beam in a direction perpendicular to the deflecting direction of said first deflector. An afocal optical system is provided between said first and second deflectors, while an imaging lens system is provided between said second deflector and the scanning surface. Said first deflector, afocal optical system and imaging lens system cooperate to displace the light beam at a constant speed in a principal scanning direction on the scanning surface, while said second deflector and imaging lens system cooperate to displace the light beam at a constant speed in an auxiliary scanning direction on said surface.
摘要:
A user private key is stored in a database of the user terminal. A user public key and user information are stored in the user management DB. The encryption/decryption unit encrypts an authority private key specific to a first authority given to a user, by using a user public key associated with user information to indicate a user. The secret sharing unit shares in secret an authority private key into two or more shared authority private keys. The encryption/decryption unit encrypts the shared authority private keys, by using an authority public key specific to each of second authorities to manage the first authority in a shared manner. The authority management DB stores the encrypted authority private key and authority public key in association with the first authority, and stores the encrypted shared authority private keys in association with the second authorities.
摘要:
A projecting apparatus comprises support device for supporting an original, a projection optical system for forming the image of the original, an optical element disposed on the image side of the projection optical system to cause a principal light ray having entered from the original through the projection optical system to travel in parallelism to the optic axis of the projection optical system, and control device for varying the imaging magnification of the original by the projection optical system with the spacing between the exit pupil of the projection optical system and the optical element being kept constant.
摘要:
An optical scanning apparatus in which a plurality of scanning light beams are deflected by a light deflector and the deflected light beams impinge onto a spherical lens having an f-.theta. characteristic at inclinations with respect to the optical axis of the lens so as to be focused on a scanning object. The apparatus is arranged to meet the following condition: ##EQU1## where, f represents the focal distance of the spherical lens (mm), .omega. represents the effective scanning rotation angle of the light deflector (deg), .DELTA.(.omega.) represents the amount of curve of the scanning line caused by the light deflecting element in the subscanning direction (mm), .rho. represents the resolution of the scan on the scanning object (lines/mm), .theta. represents the angle of inclination of any one of the light beams with respect to the optical axis of the lens within a plane which contains the optical axis of the lens and which is perpendicular to the scanning axis (deg), L represents the distance between the first reflection surface of the light deflector and the principal plane of the lens adjacent the scanning object along the optical axis (mm), and h represents the height of incidence of the any one of the light beams to the lens (mm).
摘要:
An optical information processing apparatus is provided with a unit for recording and reproducing information by projecting a main beam onto an information track on a recording medium, a unit for projecting at least two or more than two subsidiary light beams onto the information track to form light spots at different position in the transversal direction of the information track by the respective light beams and a unit for detecting the subsidiary beams reflected by the recording medium to derive a tracking signal for guiding the main beams correctly on the information track, and those light spots are larger in size in the longitudinal direction of the information track than in the transversal direction thereof.
摘要:
Disclosed is an original reading device in which, of first and second areas of the portion to be read of an original to be read which adjoin each other with a boundary therebetween, the first area is projected upon a first image pick-up element by a first lens and the second area is projected upon a second image pick-up element by a second lens, whereby the first area and the second area are read by the first element and the second element, respectively. The first and second lenses are disposed at positions corresponding to positions more toward the boundary between the first and second areas than the centers of the first and second areas.
摘要:
A scanning image forming optical system disposed in a scanning optical system includes a single lens having the both surfaces thereof divided into a light-transmitting area and a light-reflecting area, whereby the scanning optical system is compact and various aberrations in the image forming optical system is improved.
摘要:
In a secret information management system, a secret information management apparatus comprises a secret distribution unit which secretly distributes a data key k using a (k, n) threshold secret sharing scheme and creates n distributed keys B1, B2, . . . , Bn in the decryption of data D input from a user terminal, an encryption unit which creates n encrypted distributed keys EP1(B1), EP2(B2), . . . , EPn(Bn) using n distributed manager public keys P1, P2, . . . , Pn, and an encrypted data storage unit which stores encrypted data EK(D), an encrypted data key EPx(K) and the n encrypted distributed keys in association with each other.