摘要:
Obtained are an imaging optical system having a simple structure in which imaging position deviation due to deformation caused by a weight of an off-axial optical element is reduced and an image reading apparatus using the same. According to an imaging optical system for image reading, image information on an original surface is imaged on a sensor, and is read by the sensor. The imaging optical system includes reflection-type off-axial optical elements, each of which has an outer shape whose lengths in directions orthogonal to each other are different from each other and whose thickness is smaller than a length of the outer shape in a short-direction thereof and is made of a resin material. The plurality of off-axial optical elements are disposed such that mirror surfaces thereof are opposed to each other and constructed to satisfy a conditional expression.
摘要:
An image reading apparatus includes an integral scanning optical unit in which a light source device for illuminating an original placed on an original table, a plurality of mirrors for reflecting a light beam from the original and an imaging optical system for imaging the light beam reflected by the mirrors, upon a reading device, are integrally accommodated, wherein at least one mirror is so configured that the light beam is incident thereon twice or more, wherein, in a sub-scan section, reflection surfaces of the mirrors are disposed in a space at an original-reading-position side of a light entrance surface of the imaging optical system, and wherein the reflection surface of a mirror disposed at a position optically closest to the light entrance surface of the imaging optical system is placed at a position furthermost from the original table with respect to a direction of a normal thereto, as compared with the reflection surfaces of the remaining mirrors.
摘要:
Obtained are an imaging optical system having a simple structure in which imaging position deviation due to deformation caused by a weight of an off-axial optical element is reduced and an image reading apparatus using the same. According to an imaging optical system for image reading, image information on an original surface is imaged on a sensor, and is read by the sensor. The imaging optical system includes reflection-type off-axial optical elements, each of which has an outer shape whose lengths in directions orthogonal to each other are different from each other and whose thickness is smaller than a length of the outer shape in a short-direction thereof and is made of a resin material. The plurality of off-axial optical elements are disposed such that mirror surfaces thereof are opposed to each other and constructed to satisfy a conditional expression.
摘要:
A zoom lens comprises, from the object side to the image side, a first lens group, a second lens group, and a rear group including one or more lens groups, where the first and second lens groups can move at the time of zooming, and wherein the first lens group comprises, from the object side to the image side, a first lens of negative refractive power, and a second lens of positive refractive power.
摘要:
An imaging lens is used in image reading and adapted to image information of an original on a reading device. In the imaging lens at least one surface out of a plurality of surfaces forming the imaging lens has refracting power rotationally asymmetric with respect to the optical axis.
摘要:
A high thermal conductive silicon nitride sintered body of this invention is characterized by containing more than 7.5 wt % to at most 17.5 wt % of a rare earth element in terms of the amount of an oxide thereof, if necessary, at most 1.0 wt % of at least one of aluminum nitride and alumina, if necessary, 0.1-3.0 wt % of at least one compound selected from the group consisting of oxides, carbides, nitrides, silicides and borides of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and W, and at most 0.3 wt % of Li, Na, K, Fe, Ca, Mg, Sr, Ba, Mn and B as impurity cationic elements in terms of total amount thereof, containing a .beta.-type silicon nitride crystal and a grain boundary phase. The sintered body has a ratio of a crystal compound phase in the grain boundary phase to the entire grain boundary phase of at least 20%, a porosity of at most 2.5% by volume, a thermal conductivity of at least 80 W/m.multidot.K and a three-point bending strength of at least 650 MPa at a room temperature.
摘要:
A high-performance, low-cost multi-beam scanning optical device prevents picture quality from being degraded owing to the chromatic aberration of a cylindrical lens and an image formation lens system. In this multi-beam scanning optical device, a synthetic beam L.sub.0 is synthesized by a beam synthesizer from laser light beams L.sub.1 and L.sub.2, which are respectively generated by different semiconductor lasers and are different in wavelength from each other. The synthetic beam is then deflected and used for scanning. Subsequently, the synthetic beam is led through an image formation lens system to a beam splitter whereupon the synthetic beam is split into scanning light beams L.sub.3 and L.sub.4. Thereafter, images are formed from the scanning light beams L.sub.3 and L.sub.4 on a light-sensitive drum that serves as a recording medium. Further, degradation in picture quality due to the chromatic aberration is prevented by providing a grating lens, which is operative to offset or cancel out the chromatic aberration of lenses of the image formation lens system, in an optical path of the synthetic beam.
摘要:
An image forming apparatus has a first body capable of containing a movable photosensitive member therein and having first optics for applying, in a first mode, image information light obtained in the first body to the photosensitive member and forming an image on the photosensitive member, and a second body connected to the first body and having second optics for directing, in a second mode, an image information light obtained in the second body to the first body and forming an image on the photosensitive member in the first body. The width of the image formation area with respect to a direction orthogonal to the direction of movement of the photosensitive member is smaller in the second mode than in the first mode.
摘要:
An inkjet printer printing includes a cartridge mounting portion in which a ink cartridge can be inserted, and a detection portion including a detection switch having a leading end portion and detecting whether the ink cartridge is inserted in the cartridge mounting portion in accordance with a displacement amount of the leading end portion, the leading end portion being penetratingly supported via a first elastic member so as to be displaceable such that the leading end portion protrudes to the outside, and a protruding portion provided on the leading end portion side of the detection switch via a second elastic member so as to be displaceable and protrudes toward the cartridge mounting portion, the second elastic member having an elastic modulus that is smaller than an elastic modulus of the first elastic member and causing the first elastic member to be deformed when the second elastic member is deformed.
摘要:
An object is to provide an imaging optical system having a very simple structure that can read image while maintaining excellent image quality without suffering from significant asymmetrical aberrations. An imaging optical system for image reading is adapted to form an image of image information on a surface of an original onto a line sensor while changing a relative position of the original surface and the line sensor to allow the line sensor to read the image information. The imaging optical system includes two off-axial reflecting surfaces, and the two off-axial surfaces are a plus deflecting surface and a minus deflecting surface, or a minus deflecting surface and a plus deflecting surface disposed in the mentioned order from the original surface side, where an off-axial reflecting surface that deflects a reference axis beam clockwise is defined as a minus deflecting surfaces and an off axial reflecting surface that deflects the reference axis beam anticlockwise is defined as a plus deflecting surface.