An image-forming device has a plurality of cylindrical image-carrying members, and an optical scanning unit. The plurality of cylindrical image-carrying members is provided in a main casing for rotating about respective rotational axes. The rotational axes are parallel to one another and juxtaposed in a single direction. The optical scanning unit is provided in the main casing and has a plurality of laser generators, a single rotatable polygon mirror, a plurality of mirrors, and a plurality of lenses. The plurality of laser generators is provided one-to-one relationship to the plurality of image-carrying members to emit respective laser beams. The single rotatable polygon mirror deflects the respective laser beams to scan the respective image-carrying members therewith. The plurality of mirrors is provided one-to-one relationship to the plurality of image-carrying members to guide the respective laser beams along respective optical paths to the respective image-carrying members. The plurality of lenses is provided one-to-one relationship to the plurality of image-carrying members and provided in the respective optical paths and between the respective mirrors and the respective image-carrying members. Distances from the respective mirrors to the respective image-carrying members being equal to one another.

Image-forming device

A laser device capable of oscillating in a stable transverse mode and outputting a laser beam excellent in the F.F.P. A first semiconductor laser device comprises a multilayer structure in which a semiconductor layer of a first conductivity type, an active layer and a semiconductor layer of a second conductivity type different from the first one are formed in this order; and a waveguide region formed in and near the active layer for guiding the light beam in a direction perpendicular to the direction of the width by limiting the divergence of the beam in the direction of the width. The waveguide region includes a first waveguide region and a second waveguide region. In the first waveguide region, the beam is confined within the active layer because of the difference in the refractive indices between the active layer and the regions on both sides by limiting the width of the active layer; and in the second one, the beam is confined by providing an effective refractive index difference in the active layer.

Semiconductor laser device, and method of manufacturing the same

PURPOSE:To enhance the light-resistance of an image formed with a water-soluble dye, by a method wherein a silica previously surface-treated with a specific metallic compound is contained in the recording surface of a material to be recorded. CONSTITUTION:In a material to be recorded with an image by using a recording liquid containing a water-soluble dye, a silica surface-treated with one of a metallic soap, a hydroxide, a salt, and an oxide of a metal selected from among groups composed of Na, R, Ca, Mg, Al, Zn, Ba, Sr, or Sn or a mixture of two or more of the above compounds is contained. As a particularly preferable method for treating the silica with these compounds, a method wherein the metallic compound is added in the initial stage or the latter stage of aging reaction or gelation in the manufacturing process of the silica or a method wherein it is added in the initial stage of the reaction is employed. To contain the surface-treated silica in a substrate, for example, a method wherein the surface-treated silica is added in a paper making process to manufacture a paper is employed. This material to be recorded is manufactured by a method wherein the treated silica is added to a coating liquid and the coating liquid is coated on the substrate such as a paper and dried.

Material to be recorded

A thermally responsive valve assembly (134) for scroll motor-compressor high temperature protection, which causes a high-side to low-side leak when excessive discharge gas temperatures are encountered, thereby causing the motor protector (35) to trip and de-energize the motor. The valve assembly (134) includes means for ducting (200) the excessive temperature discharge gas to the lower portion of the motor/compressor shell (10) to the motor to circulate the high temperature gas throughout the motor cavity. The excessive temperature discharge gas heats the motor stator (20) and windings (32) which will in turn cause the motor protector (35) to trip and de-energize the motor.

Scroll machine with overheating protection

A semiconductor laser device includes a base, a semiconductor laser chip and a resin layer enclosing the semiconductor laser chip. The base may have a monitor photodiode chip mounted thereon in the vicinity of the semiconductor laser chip. The resin layer enclosing the semiconductor laser chipor both of the semiconductor laser chip and the monitor photodiode chip is made of a single synthetic resin having a thickness not greater than 500µm and also having a surface substantially parallel to an outwardly oriented beam emitting end face of the semiconductor laser chip.

Semiconductor laser device.

PURPOSE:To enable a current constricting structure to be formed in self-alignment with an optical waveguide structure and to prevent the increase in contact resistance between a contact layer and an electrode and the deformation of the electrode, by providing a contact layer having a second type of conductivity on a clad layer having the second type of conductivity and a current blocking layer. CONSTITUTION:A semiconductor laser device according to the present invention comprises a semiconductor substrate 11 having a first type of conductivity, a clad layer 14 having the first type of conductivity, an active layer 15 and clad layers 16-18 having a second type of conductivity and having a linear projection 18 thereon. A double hetero junction structure is thus formed on the semiconductor substrate 11. The semiconductor laser device further comprises a current blocking layer 21 formed on this double hetero junction structure except at least a part of the projection 18 of the clad layers having the second type of conductivity, and contact layers 20 and 22 having the second type of conductivity and formed on the second-conductivity-type clad layers 16-18 and the current blocking layer 21. For example, the semiconductor substrate 11 and the contact layers 20 and 22 may be formed of GaAs and the double hetero junction structure 14-18 may be formed of InGaAlP. Further, an InGaP buffer layer 13 of the first type of conductivity is provided between the GaAs substrate 11 and the InGaAlP clad layer 14 having the first type of conductivity.

Semiconductor laser device and manufacture thereof

PURPOSE:To improve element characteristics and reliability, by constituting a second conductivity type clad layer forming a stripe type protrusion as a three-layered structure, and making the band gap of a second clad layer smaller than that of a first clad layer and that of a third clad layer, and larger than that of an active layer. CONSTITUTION:A DH structure part constitured of an N-GaAs substrate 11, an N-InGaAlP clad layer 14, an InGaP active layer 15, and a P-InGaAlP clad layer having a stripe protrusion is formed on the substrate 11. A semiconductor laser is formed of an N-GaAs current blocking layer 21 which is formed on the DH structure part except the clad layer protrusion, and P-GaAs contact layers 20, 22 formed on the P-InGaAlP clad layer. The P-InGaAlP clad layer is formed as a three-layered structure. The band gap of an intermediate second clad layer 17 is made smaller than that of a first clad layer 16 and that of a third clad layer 18 and larger than that of the active layer 15. Thereby element characteristics and reliability can be improved.

Hideto Kanbara

Papers

Semiconductor laser device and manufacture thereof

Semiconductor laser device and its manufacture