Abstract: A projection optical system having a plurality of reflecting surfaces is disclosed in which a sufficiently large angle is provided between an incident side reference axis and an emerging side reference axis while tilt angles of the respective reflecting surfaces can remain small. The projection optical system projects luminous flux from an image forming element which forms an original image onto a projection surface. The incident side reference axis and the emerging side reference axis of the projection optical system are oblique to each other. The projection optical system has a plurality of reflecting surfaces each having a curvature. The reflecting surfaces are arranged such that the reference axis has at least one intersection in the projection optical system.

Abstract: A projection optical system which can project a bright image with less distortion and a small projection distance without causing aberration or an increase in size of reflective surfaces is disclosed. The projection optical system projects luminous flux from an original image onto a projection surface which is oblique to a central principal ray which is a principal ray of luminous flux traveling from the center of the original image to the center of a projected image. The projection optical system comprises a refractive optical system which includes a plurality of refractive optical elements through which the luminous flux from the original image passes through, and a reflective optical system which includes a plurality of reflective surfaces each having an optical power and guides the luminous flux emerging from the refractive optical system to the projection surface.

Abstract: There are provided a suction unit which sucks a recording medium, and a unit which changes sucking force of the suction unit according to the property of the recording medium. Hereby, since the sucking force of the suction unit can be set according to a state of the recording medium. Therefore, for example, even if the recording medium is greatly curled, since its recording medium can be surely sucked on the transporting surface of the recording medium by the suction unit. Further, even if the recording medium has little rigidity and is thin, it is possible to prevent the recording medium from being stuck on the transporting surface of the recording medium by the suction unit.

Abstract: A sucking device having a fixed material transportation surface including plural sucking holes, a decompression chamber connecting to the plural sucking holes, and a sucking device sucking air in the decompression chamber is set at discharging side of the fixed material. The fixed material is fed on the fixed material transportation surface of the sucking device by the delivering device, and is stuck on the fixed material transportation surface through the sucking holes by the sucking device. The fixed material is fixed by a fixing head at the state being stuck and is transported gradually to a downstream side from an upstream side by the delivering device on the fixed material transportation surface. After that, when fixing is finished, the fixed material separates from surface of the fixed material transportation surface and rises slightly by blowing air from the sucking holes by a blowing device so as to move to discharging direction, that is, the downstream side by an auxiliary transporting device.

Abstract: A projection optical system which has a short projection distance and a compact structure, and allows oblique projection. The projection optical system projects luminous flux from an image forming element for forming an original image onto a projection surface which is oblique to a central principal ray which is a principal ray of luminous flux traveling from the center of the original image to the center of a finally formed image. The system includes a plurality of reflecting surfaces each having a curvature. In addition, the projection optical system satisfies a predetermined expression (1).

Abstract: A carriage, on which a recording head is mounted, and to which a moving unit is connected, reciprocates a recording area by the moving unit to perform recording by the recording head. In the carriage, a recording head mount part and a connection part to the moving unit are separately provided, and the mount part and the connection part are coupled by a coupling structure having a linear elastic member. Hereby, vibration from the moving unit is shielded in the division portion and is not transmitted to the recording head mount part. Therefore, recording accuracy of the recording head can be kept in a high state.

Abstract: An influence by a light quantity distribution of light irradiating means in a fingerprint image is decreased, so that an excellent fingerprint image improved in contract can be obtained. Light irradiating means for irradiating a light on a finger arranged on a predetermined region, and a solid state image pickup element for receiving a diffused light from the inside of the finger by the light irradiated from this light irradiating means and for picking up the fingerprint image of the finger is provided, and the light irradiating means is arranged across a length at least equal to or more than an effective reading length (L) of the solid state image pickup element.

Abstract: Actuator units independently dedicated to nozzles divided into a plurality of groups are fixed to a common flow path unit having the nozzles formed therein with through holes aligned with one another. Heads of various types can be formed by using the actuator units of the same design only by changing the mode of arrangement of the nozzles in accordance with the purpose.

Abstract: A liquid ejection head is operable to eject a liquid droplet toward a medium at a liquid ejection point A first roller transports the medium toward the liquid ejection point. A second roller ejects the medium transported from the liquid ejection point to the outside of the apparatus. At least one detection roller is directly brought into contact with the medium and is rotated in accordance with the transportation of the medium, the at least one detection roller being disposed in the vicinity of at least one of the first roller and the second roller. A detector detects a rotation amount of the detection roller. A controller controls the transportation of the medium in accordance with the rotation amount.

Abstract: Actuator units independently dedicated to nozzles divided into a plurality of groups are fixed to a common flow path unit having the nozzles formed therein with through holes aligned with one another. Heads of various types can be formed by using the actuator units of the same design only by changing the mode of arrangement of the nozzles in accordance with the purpose.

Abstract: A follower roller is brought into press contact with a driving roller by a load having a predetermined value, thereby being rotated in accordance with a rotation of the driving roller to transport the medium clamped therebetween in a first direction. The follower roller includes a shaft portion and a roller body provided so as to surround the shaft portion. The follower roller is configured such that a value of a ratio f/F is not greater than 0.03. Here, F is a force transporting the medium in the first direction which is generated by the load, and f is a resistance force generated in a second direction opposite to the first direction by a friction loss of the shaft portion of the follower roller which is generated by the load.

Abstract: Actuator units independently dedicated to nozzles divided into a plurality of groups are fixed to a common flow path unit having the nozzles formed therein with through holes aligned with one another. Heads of various types can be formed by using the actuator units of the same design only by changing the mode of arrangement of the nozzles in accordance with the purpose.

Abstract: On a medium transporting surface, a dimple extending continuously from a transportation upstream end of a medium to a transportation downstream end are formed. Hereby, a leading end of the medium, after pulled into the dimples once, is transported in the pulled state. Therefore, it is prevented that the leading end of the medium is curled up by a conventional partition wall provided in the direction perpendicular to the medium transporting direction, so that it is possible to prevent a stain on the medium caused by contact with a recording head.

Abstract: A printing method comprises the steps of: in a first movement, moving a print head to form dots on a medium at aperiodic intervals in a moving direction of the print head, wherein the print head includes N pieces of nozzles arranged at a constant pitch in a direction that intersects with the moving direction, wherein the N pieces of nozzles are for forming N dots of a same color, and wherein N is an integer of at least two; in second through M-th movements, moving the print head to form, on the medium, the rest of the dots that were not formed in the first movement, wherein M is an integer of at least two; and repeating the first through M-th movements to print information on the medium.

Abstract: There are provided a sucking unit having a recording medium transportation surface including a plurality of sucking holes, a decompression chamber communicating with the sucking holes and a sucking device for sucking air in the decompression chamber, and a delivering device for adsorbing a recording medium supplied onto the recording medium transportation surface of the sucking unit onto the recording medium transportation surface through the sucking hole by the sucking device, and delivering the recording medium from an upstream side of the sucking unit to a downstream side thereof. Each sucking hole of the sucking unit is formed by a through hole section communicating with the decompression chamber and a sucking chamber having a larger area of a sucking surface opposed to the recording medium than a sectional area of the through hole section.

Abstract: Of suction holes formed on a medium transporting surface, the areas of the suction holes formed in positions corresponding to ends of a medium which is being transported are set larger than the areas of other suction holes. Hereby, since large air flow is obtained under the both side ends or the leading end of the medium, the medium is transported in a state where the both side ends or the leading end are attracted into the suction holes, and a stain due to contact with a recording head can be prevented.

Abstract: There are provided a suction unit which sucks a recording medium, and a unit which changes sucking force of the suction unit according to the property of the recording medium. Hereby, since the sucking force of the suction unit can be set according to a state of the recording medium. Therefore, for example, even if the recording medium is greatly curled, since its recording medium can be surely sucked on the transporting surface of the recording medium by the suction unit. Further, even if the recording medium has little rigidity and is thin, it is possible to prevent the recording medium from being stuck on the transporting surface of the recording medium by the suction unit.

Abstract: A projection optical system having a plurality of reflecting surfaces is disclosed in which a sufficiently large angle is provided between an incident side reference axis and an emerging side reference axis while tilt angles of the respective reflecting surfaces can remain small. The projection optical system projects luminous flux from an image forming element which forms an original image onto a projection surface. The incident side reference axis and the emerging side reference axis of the projection optical system are oblique to each other. The projection optical system has a plurality of reflecting surfaces each having a curvature. The reflecting surfaces are arranged such that the reference axis has at least one intersection in the projection optical system.

Abstract: A projection optical system which has a short projection distance and a compact structure, and allows oblique projection. The projection optical system projects luminous flux from an image forming element for forming an original image onto a projection surface which is oblique to a central principal ray which is a principal ray of luminous flux traveling from the center of the original image to the center of a finally formed image. The system includes a plurality of reflecting surfaces each having a curvature. In addition, the projection optical system satisfies a predetermined expression (1).

Abstract: A projection optical system which can project a bright image with less distortion and a small projection distance without causing aberration or an increase in size of reflective surfaces is disclosed. The projection optical system projects luminous flux from an original image onto a projection surface which is oblique to a central principal ray which is a principal ray of luminous flux traveling from the center of the original image to the center of a projected image. The projection optical system comprises a refractive optical system which includes a plurality of refractive optical elements through which the luminous flux from the original image passes through, and a reflective optical system which includes a plurality of reflective surfaces each having an optical power and guides the luminous flux emerging from the refractive optical system to the projection surface.