Abstract: A method for performing data communication between two circuits is provided. The method comprises the steps of: serially transmitting information between two circuits, determining a first level change in one direction of a pulse signal output from one of the circuits to the other as a reference time, judging whether a first data bit is "1" or "0" in accordance with a time period from the reference time to a second level change in the one direction following the reference time, and determining the second level change in the one direction as the reference time relative to the next bit of data in the pulse signal, whereby data of a predetermined number of bits are continuously transmitted.

Abstract: A switching arrangement for activating a plurality of electrical devices connected to a communication line. The switching arrangement monitors the communication line for the reception of activation signals, and also transmits activation signals to the communication line. The switching arrangement activates an electrical device (from the plurality of electrical devices) connected to the communication line, in response to the detection of the an activation signal, to shift the electrical device from a dormant state (in which electrical consumption by the electrical device is minimized) to a normal, functional operational state (in which a maximum electrical consumption of the electrical device occurs) only when the electrical device is actually being operated. By switching the electrical device between a dormant state and an operational state, the amount of electrical power required to operate the plurality of electrical devices is reduced.

Abstract: A lens holding structure used in a camera is provided having a rectangular photographing aperture. The lens holding structure includes a lens and a lens holding member for holding a lens. The lens is formed having a pair of flat surfaces, parallel to each other, and parallel to a longitudinal boundary of the photographing aperture. The lens holding member has a lens holding sleeve and a pair of lens engaging arms. When the lens is fitted into the lens holding sleeve, the lens engaging arms contact the pair of flat surfaces of the lens.

Abstract: An automatic focusing projector has a reflector which includes a semispherical mirror and a semielliptical mirror in combination, and a contrast chart having a contrast pattern associated with the reflector. The first focal point of the semielliptical mirror is identical to the center of the semispherical mirror. The contrast pattern is located between the first and second focal points of the semielliptical mirror. A light source is provided in the vicinity of the first focal point of the semielliptical mirror. The light source can be a white light source, and a colored filter can be positioned forwardly of a projecting lens which forms part of the projector in order to pass light having a wavelength region of low luminosity in which a human eye is virtually insensitive.

Abstract: An imaging system including apparatus for forming a latent image on a surface, the latent image including a first portion having a high level of electrostatic charge, a second portion having a low level of electrostatic charge and a third portion having an intermediate level of electrostatic charge, and apparatus for developing the latent image by contacting it with a liquid toner composition comprising an insulating, nonpolar liquid having admixed therewith a first type of pigmented particles having charges of a first polarity and a second type of pigmented particles having charges of an opposite polarity, such that the first type of pigmented particles becomes deposited onto the first portion and the second type of pigment particles becomes deposited onto the second portion.