Abstract: A vibration driven motor has a rail-like stator secured to a bottom plate and a vibration member for generating a travelling vibration wave in an elastic member to which an electro-mechanical energy conversion element is fixed due to an application of AC electric field to the electro-mechanical energy conversion element so as to bring a portion of the elastic member into press-contact with the rail-like stator. In the vibration driven motor a surface area of the bottom portion of the rail-like stator which comes in contact with the bottom plate is less than the a surface area of the top portion of the rail-like stator.

Abstract: Disclosed is feeding apparatus comprising a first vibration apparatus having projections provided with a predetermined distance therebetween, the first vibration apparatus producing a first travelling vibration wave in response to an electrical signal applied thereto, and a second vibration apparatus having projections located at the positions substantially corresponding to the projections of the first vibration apparatus, the second vibration apparatus producing a second travelling vibration wave proceeding in the same direction as the first travelling vibration wave in response to an electrical signal supplied thereto thereby the sheet inserted between the projections of the first vibration apparatus and the projections of the second vibration apparatus being fed by the first and second travelling vibration waves.

Abstract: An object measuring apparatus uses lightwave interference by coherent beams. A single light beam having two lightwave components with a phase difference that changes in time is divided so that one lightwave component is applied to the object and the other lightwave component is applied to a reference surface. The lightwave components for the object and the reference surface are interfered with each other and a change in the interference light is detected.

Abstract: A vibration wave driven motor having a vibratory elastic member provided with an electro-mechanical energy conversion element, and a rail-type stator on which the elastic vibratory member is resiliently pressed by, for example, springs. When A.C. power is supplied to the electro-mechanical energy conversion element, a traveling vibration wave is generated in the elastic vibratory member so that a frictional force is produced to act between the stator and the elastic member so as to cause a relative movement between the elastic vibratory member and the stator. At least one of the sliding surface of the elastic vibratory member and the sliding surface of the stator has a smoothly curved configuration, so as to improve the durability of the motor.

Abstract: An improved sheet feeding device of this invention includes a variable pressure applying unit for changing a contact pressure between a sheet and vibration members.

Abstract: There is disclosed a sheet feeding device having at least two vibration members pinching a sheet, which is frictionally driven by the travelling vibration waves generated in the vibration members. The device is further provided with a detector for detecting the state of vibration of the vibration members and generating a signal corresponding to the phase difference between the vibrations. The signal is used for correcting the vibration state of the vibrations members, thus significantly reducing the unevenness in the sheet feeding.

Abstract: There is disclosed a sheet feeding device having a vibration member for generating vibration for feeding a sheet member. The vibration member is in frictional engagement with the sheet member, which is fed by vibration generated in the vibration member. The device further has a member for controlling the amplitude of the vibration of the vibration member according to the feeding speed of the sheet member whereby the sheet can be fed with a desired speed.

Abstract: A position detecting device for detecting the position of an object includes an illumination optical system for producing a light beam and for irradiating the object with the light beam, an optical system for focusing the light beam, a focus position controlling system operative to change the position at which the light beam is focused by the focusing optical system, a first detecting device for receiving the light beam reflected from the object to detect the state of incidence of the light beam on the object, and a second detecting device for detecting the position of the object on the basis of the detection of the state of incidence of the light beam on the object by the first detecting means.

Abstract: There is disclosed a variable focal length lens comprising: an optical element showing substantially different refraction characteristics depending on polarization characteristics of an incident light beam, first optical unit for controlling the polarization characteristics of the beam incident on said optical element; and second optical unit for controlling the polarization characteristics of the light subjected to predetermined refraction by the optical element, the second optical unit being interlocked with the first optical unit.

Abstract: A variable focal length lens has a lens system having optical anisotropy, a polarization plane control device for changing the direction of polarization of a light beam on the lens system. A detector is provided for detecting the direction of polarization of the light beam emergent from the lens or the polarization plane control device which, by a signal, controls the polarization plane control device so that only a light beam of desired direction of polarization emerges from the lens.

Abstract: An optical output device comprising a deflector having an electrooptic crystal element provided with an electrode and controlling an electric field applied to the electrode to vary the deflection angle of a light beam passing through the crystal and projecting the beam upon a predetermined position on a recording medium and separating the reflected light from the recording medium from the light beam or/and a variable focal length lens consisting of an electrooptic crystal and which uses a condenser for controlling the focal length of the lens by an electric field applied to the crystal and focusing the light beam to the recording medium, thereby reducing the number of mechanically movable parts of the device.

Abstract: Disclosed is a variable-focal-length lens whose focal length can be electrically controlled by applying an electric field of uniform intensity distribution to a compound lens including at least one lens formed of electrooptic crystal and varying the intensity of the applied electric field.

Abstract: A novel arrangement of variable-focal-length lens using an electrooptic effect is provided. A variable electric field is applied to an electrooptic crystal to produce therein a refractive index distribution having a lens action. The applied electric field is such that the intensity distribution of the lens varies along one direction in a plane normal to the direction of the light incidence but which has a uniform intensity distribution in the direction normal to this direction. A two-dimensional variable-focal-length lens is obtained by combining two such one-dimensional lenses in such manner that the two-lenses intersect each other at right angles with respect to the direction of the lens action. Also, a refractive index distribution having a two-dimensional lens action is produced to form a variable-focal-length lens when an electric field having an intensity distribution which varies within the plane normal to the direction of the incident light is applied to the electrooptic crystal.