摘要:
An electrophotographic printing machine is provided with a photoreceptor drum including a transparent cylindrical base having a transparent electrically conductive layer and a photoconductive layer laminated in this order on a surface thereof and a dielectric belt in contact with the photoconductive layer. The photosensitive layer is exposed while voltage is being applied across an electrically conductive toner and a transparent electrically conductive layer, thereby forming a toner image on the photosensitive layer. After the toner image on the photosensitive layer is transferred to the dielectric belt which temporarily carries the toner image, the copying material is superimposed on the toner image, and heat and pressure are applied to the toner image respectively from a heater and a pressurizing roller. Since the melted toner is transferred onto the copying material using the adherence of the transfer sheet without using electric Coulomb force, the efficiency in transferring the toner image to the copying material is not affected by the electric surface resistance of the copying material. An image can therefore be formed using the electrically conductive toner even on a copying material of low electric surface resistance such as a normal transfer sheet.
摘要:
There are provided a light-emitting device for use in a backlight unit of a display apparatus equipped with a display panel, which can be made lower in profile and is capable of applying light to the display panel with uniformity in the brightness of the display panel in the planar direction of the display panel, as well as a display apparatus equipped with the light-emitting device. A backlight unit includes a printed substrate, a plurality of light-emitting sections each having a base support, an LED chip and a lens, and a reflective member surrounding the light-emitting section. A specular reflection portion is formed in a first reflective region of the reflective member.
摘要:
An optical scanning device cover, covering an upper portion of an optical scanning device, includes an exposure window, a close stopper, an open stopper, and a rotation cam plate. A projection to be held in a link portion of a rotation cam is fixedly provided on a shutter. When the rotation cam is rotated in a direction of an arrow R(1) from a state in which the shutter is closed, A-side of the shutter turns until the shutter comes into contact with the open stopper to open that side of shutter, and thereafter, the B-side of the shutter turns to open that side of the shutter.
摘要:
A laser scanning optical system converts a plurality of beams emitted from the laser diode (LD) into parallel light using a collimator lens, shapes the parallel light using an aperture, and executes exposure of a plurality of lines simultaneously on a photoreceptor drum. To cause a necessary emitting point interval d determined uniquely from the magnification of the optical system to coincide with an emitting point interval of the LD used, the LD is rotated by an angle θ against the main optical axis plane thereof. In this case, a converting device that converts the aspect ratio of a profile of the light beam emitted from the LD is provided. A conversion characteristic of the converting device is adjusted such that the characteristic is matched with a condition within a predetermined region following a characteristic of the optical system.
摘要:
An optical scanning unit irradiates a polygon mirror with a plurality of light beams emitted from a light source according to image data, and scans and exposes a plurality of photoreceptors with the plurality of light beams as scanning lights. The optical scanning unit comprises a primary optical system unit including an optical system that emits the plurality of light beams, which are emitted from the light source toward the polygon mirror, and a secondary optical system unit including an optical system that emits the light beams, which are reflected by the polygon mirror toward the photoreceptors. The arrangement is such that the primary optical system unit is fitted removably to the secondary optical system unit, and that a combined unit of the primary optical system unit and the secondary optical system unit is removably fitted to an image forming apparatus having the photoreceptors.
摘要:
In an exposure unit including: a laser scanning unit emitting a multiple number of beams; a polygon mirror for deflecting the multiple beams by reflection with the same facet; an optical system including optical elements for leading the beams correspondingly to a multiple number of photoreceptor drums laid out along an auxiliary scan direction, the bottom of a casing of the exposure unit to which the polygon mirror and the optical elements arranged along the directions of the beams emitted from the polygon mirror are attached is constructed so that the attachment portions of individual optical elements for each beam are differentiated in thickness from the areas where no attachment portion is formed.
摘要:
An optical scanning unit irradiates a polygon mirror with a plurality of light beams emitted from a light source according to image data, and scans and exposes a plurality of photoreceptors with the plurality of light beams as scanning lights. The optical scanning unit comprises a primary optical system unit including an optical system that emits the plurality of light beams, which are emitted from the light source toward the polygon mirror, and a secondary optical system unit including an optical system that emits the light beams, which are reflected by the polygon mirror toward the photoreceptors. The arrangement is such that the primary optical system unit is fitted removably to the secondary optical system unit, and that a combined unit of the primary optical system unit and the secondary optical system unit is removably fitted to an image forming apparatus having the photoreceptors.
摘要:
A capacitive load driving circuit (1) for charging and discharging a capacitive load (11) is provided with a voltage divider (5) for dividing a power supply voltage (VH) into a plurality of different voltages (V1–V9), a plurality of condensers (2a–i) to which the voltages (V1–V9) are respectively charged as terminal voltages, and a switch (7) for switching connections between the capacitive load (11) and the condensers (2a–i), the switch (7) sequentially connecting the condensers (2a–i) in an ascending order of the terminal voltages so that electrostatic energy is supplied to the capacitive load (11) when the capacitive load (11) is charged, the switch (7) sequentially connecting the condensers (2a–i) in a descending order of the terminal voltages so that electrostatic energy is collected from the capacitive load (11) when the capacitive load (11) is discharged. With this, it is possible to provide a capacitive load drive circuit having a simple circuit configuration and capable of efficiently collecting and reusing energy accumulated in the capacitive load, and a capacitive load driving method.
摘要:
A measuring device for amount of charge of developer includes an upper electrode, a lower electrode provided under the upper electrode, which are provided in parallel so as to face each other, flying electric field voltage application unit for applying a flying electric field voltage to the upper electrode, for generating an electric field so as to fly developer from the lower electrode to the upper electrode, current detection unit for detecting a current flowing in the upper electrode, and arithmetic unit for computing a total amount of charge of the developer adhering to the upper electrode based on a change in amount of current detected by the current detection unit, wherein a current that generates as a toner T adheres to the upper electrode is detected by the current detection unit, and based on a change in amount of the current, a total amount of charge of the developer adhering to the upper electrode is computed by the arithmetic unit. As a result, the measuring device for amount of charge of developer can be obtained at low cost.
摘要:
A measuring device for an amount of charge of toner including countered first and second electrodes for forming an electric field which accelerates toner particles, a voltage generator for applying a voltage across the first and second electrodes, a magnifying optical system for magnifying the image of toner particles which move between the first and the second electrodes, a light source for illuminating a vicinity of a focus of the magnifying optical system, a CCD sensor for receiving an optical image of the toner particles magnified by the magnifying optical system so as to convert the optical image into an image signal and a CPU for controlling a voltage from the voltage generator based upon the image signal so that the toner particles pass a prescribed position in the vicinity of the focus of the magnifying optical system and for obtaining an amount of charge of toner particles from a value of the voltage, and an image forming apparatus in which the measuring device is installed. The measuring device for an amount of charge of toner becomes compact, so it can be installed in an image forming apparatus.