Abstract: Provided is a surface emitting laser array using a photonic crystal, which allows an active layer to be shared without disconnecting the active layer between the individual surface emitting lasers adjacent to each other, and enables high-density arraying easily. The surface emitting laser array includes: at least two surface emitting lasers formed on a substrate, each having a laminated structure of multiple semiconductor layers including a semiconductor multilayer mirror, an active layer, and a photonic crystal having a refractive index profile in an in-plane direction, the photonic crystal and the semiconductor multilayer mirror in the laminated structure forming a waveguide for guiding light in a resonance mode; and a region without the photonic crystal provided between adjacent surface emitting lasers in the surface emitting laser array, in which the surface emitting lasers have the same semiconductor multilayer mirror and the same active layer.

Abstract: A surface-emitting laser includes a surface relief structure provided on an upper multilayer reflector, the surface relief structure including a region of a first laminate, a region of a second laminate that has a larger optical thickness than the first laminate, and a region of a third laminate that has a larger optical thickness than the first laminate and the second laminate.

Abstract: Provided is a high-output surface-emitting laser capable of reducing effects on reflectance of an upper reflection mirror in a single transverse mode. The surface-emitting laser includes plural semiconductor layers, laminated on a substrate, which includes a lower semiconductor multilayer reflection mirror, an active layer, and an upper semiconductor multilayer reflection mirror, wherein the lower or upper semiconductor multilayer reflection mirror includes a first semiconductor layer having a two-dimensional photonic crystal structure comprised of a high and low refractive index portions which are arranged in a direction parallel to the substrate, and wherein a second semiconductor layer laminated on the first semiconductor layer includes a microhole which reaches the low refractive index portion, the cross section of the microhole in the direction parallel to the substrate being smaller than the cross section of the low refractive index portion formed in the first semiconductor layer.

Abstract: Provided is an electrophotographic image forming apparatus using a novel array light source to replace the LED array light sources, which enables provision of a reduced image formation spot diameter on a photoreceptor as well as a reduced spot pitch. An electrophotographic image forming apparatus according to the present invention includes an electrophotographic image forming apparatus including a light source, and an electrophotographic photoreceptor to be exposed by the light source, the light source for exposing the electrophotographic photoreceptor including: a plurality of surface plasmon waveguides for forming a potential distribution on the electrophotographic photoreceptor using near-field light generated at tips thereof, the surface plasmon waveguides being arrayed: and an excitation mechanism for exciting a surface plasmon on each of the plurality of surface plasmon waveguides.

Abstract: When configuring a surface emitting laser by a semiconductor material not capable of largely extracting a refractive-index difference, the surface emitting laser using a photonic crystal capable of forming a waveguide is provided.

Abstract: Provided is a surface emitting laser or the like capable of suppressing horizontal misalignment between the surface relief structure and the current confining structure to make higher the precision of the alignment, to thereby obtain single transverse mode characteristics with stability. The surface emitting laser having a semiconductor layer laminated therein includes: a first etching region formed by etching a part of the upper mirror; and a second etching region formed by performing etching from a bottom portion of the first etching region to a semiconductor layer for forming a current confining structure, in which a depth of the second etching region is smaller than a depth of the first etching region.

Abstract: A surface emitting laser comprises an underlayer, an active layer formed on the underlayer, a slab layer formed on the active layer and having a photonic crystal structure optically combined with the active layer, and a metal thin film formed on the slab layer and having a periodic fine structure; and enabling taking-out of the light beam propagating in a layer-plane direction in the slab layer through the metal thin film.

Abstract: Provided is a surface emitting laser manufacturing method, etc., which reduces process damage occurring to a surface relief structure, enabling stable provision of a single transverse mode characteristic. Provided is a method including a surface relief structure for controlling a reflectance in a light emitting portion of an upper mirror, the surface relief structure including a stepped structure, includes: forming a resist pattern including a pattern for forming a mesa structure and a pattern for forming a stepped structure, on or above the upper mirror, and performing first-phase etching for etching the surface layer of the upper mirror to determine the horizontal position of the stepped structure; forming a current confining structure after the performing first-phase etching; and performing second-phase etching for further etching the area that the first-phase etching has been performed, to determine the depth position of the stepped structure, after the forming a current confining structure.

Abstract: Provided is a surface emitting laser or the like capable of suppressing horizontal misalignment between the surface relief structure and the current confining structure to make higher the precision of the alignment, to thereby obtain single transverse mode characteristics with stability. The surface emitting laser having a semiconductor layer laminated therein includes: a first etching region formed by etching a part of the upper mirror; and a second etching region formed by performing etching from a bottom portion of the first etching region to a semiconductor layer for forming a current confining structure, in which a depth of the second etching region is smaller than a depth of the first etching region.

Abstract: A surface emitting laser includes a lower multilayer mirror, an active layer, and an upper multilayer mirror stacked onto a substrate. A first current confinement layer having a first electrically conductive region and a first insulating region is formed above or below the active layer using a first trench structure. A second current confinement layer having a second electrically conductive region and a second insulating region is formed above or below the first current confinement layer using a second trench structure. The first and second trench structures extend from a top surface of the upper multilayer mirror towards the substrate such that the second trench structure surrounds the first trench structure. When the surface emitting laser is viewed in an in-plane direction of the substrate, a boundary between the first electrically conductive region and the first insulating region is disposed inside the second electrically conductive region.

Abstract: A surface emitting laser includes a lower multilayer mirror and an upper multilayer mirror which are provided on a substrate. A first oxidizable layer is partially oxidized to form a first current confinement layer including a first conductive region and a first insulating region. A second oxidizable layer is partially oxidized to form a second current confinement layer including a second conductive region and a second insulating region, a boundary between the first conductive region and the first insulating region being disposed inside the second current confinement layer in an in-plane direction of the substrate. The first oxidizable layer and the second oxidizable layer or layers adjacent to the respective oxidizable layers are adjusted so that when both layers are oxidized under the same oxidizing conditions, the oxidation rate of the first oxidizable layer is lower than that of the second oxidizable layer.

Abstract: Provided is a method for manufacturing a surface-emitting laser capable of forming a photonic crystal structure inside a semiconductor highly accurately and easily without direct bonding. It is a method by laminating on a substrate a plurality of semiconductor layers including an active layer and a semiconductor layer having a photonic crystal structure formed therein, the method including the steps of forming a second semiconductor layer on a first semiconductor layer to form the photonic crystal structure, forming a plurality of microholes in the second semiconductor layer, forming a low refractive index portion in a part of the first semiconductor layer via the plurality of microholes thereby to provide the first semiconductor layer with the photonic crystal structure having a one-dimensional or two-dimensional refractive index distribution in a direction parallel to the substrate, and forming a third semiconductor layer by crystal regrowth from a surface of the second semiconductor layer.

Abstract: A surface emitting laser having a photonic crystal layer 130 on a substrate 105 with an active layer therebetween, in which the photonic crystal layer includes at least a first periodic structure for resonating in an in-plane direction and a second periodic structure for modulating a light intensity distribution in an in-plane direction. The light intensity in the photonic crystal layer is periodically distributed to a region having high light intensity and a region having low light intensity by the second periodic structure. Further, a conductive film 170 for performing current injection into the active layer is selectively provided just above the region having low light intensity. The surface emitting laser provides suppression of light absorption and highly efficient current injection into an active layer to attain a high power.

Abstract: A surface emitting laser which oscillates at a wavelength ? of a blue band, including a photonic crystal layer including a photonic crystal structure, an active layer provided on one surface of the photonic crystal layer, and an electrode provided on the other surface of the photonic crystal layer for injecting electric current into the active layer. The photonic crystal structure has a thickness of 100 nm or more. A laser beam is emitted toward a direction opposite to a side of the photonic crystal layer on which the electrode is provided.

Abstract: Provided is a surface emitting laser manufacturing method, etc., which reduces process damage occurring to a surface relief structure, enabling stable provision of a single transverse mode characteristic. Provided is a method including a surface relief structure for controlling a reflectance in a light emitting portion of an upper mirror, the surface relief structure including a stepped structure, includes: forming a resist pattern including a pattern for forming a mesa structure and a pattern for forming a stepped structure, on or above the upper mirror, and performing first-phase etching for etching the surface layer of the upper mirror to determine the horizontal position of the stepped structure; forming a current confining structure after the performing first-phase etching; and performing second-phase etching for further etching the area that the first-phase etching has been performed, to determine the depth position of the stepped structure, after the forming a current confining structure.

Abstract: Provided is a process for producing a surface emitting laser including a surface relief structure provided on laminated semiconductor layers, including the steps of transferring, to a first dielectric film, a first pattern for defining a mesa structure and a second pattern for defining the surface relief structure in the same process; and forming a second dielectric film on the first dielectric film and a surface of the laminated semiconductor layers to which the first pattern and the second pattern have been transferred. Accordingly, a center position of the surface relief structure can be aligned with a center position of a current confinement structure at high precision.

Abstract: The present invention provides a surface emitting laser having a novel structure which eliminates necessity to provide a low refractive index medium at an interface of a photonic crystal layer on the side of a substrate. A multilayer mirror (1300), an active layer (1200), and a refractive index periodic structure layer (1020) whose refractive index changes periodically are laminated in a direction perpendicular to a substrate (1500). The refractive index periodic structure layer is structured so as to separate a light having a wavelength ? perpendicularly incident on the refractive index periodic structure into at least a transmitted light and a diffracted light. The multilayer mirror is structured so as to have a reflectance with regard to the diffracted light higher than a reflectance with regard to the transmitted light. A resonant mode is realized within a waveguide including the refractive index periodic structure layer and the multilayer mirror.

Abstract: Provided is a process for producing a surface emitting laser including a surface relief structure provided on laminated semiconductor layers, including the steps of transferring, to a first dielectric film, a first pattern for defining a mesa structure and a second pattern for defining the surface relief structure in the same process; and forming a second dielectric film on the first dielectric film and a surface of the laminated semiconductor layers to which the first pattern and the second pattern have been transferred. Accordingly, a center position of the surface relief structure can be aligned with a center position of a current confinement structure at high precision.

Abstract: The present invention provides a surface emitting laser having a novel structure which eliminates necessity to provide a low refractive index medium at an interface of a photonic crystal layer on the side of a substrate. A multilayer mirror (1300), an active layer (1200), and a refractive index periodic structure layer (1020) whose refractive index changes periodically are laminated in a direction perpendicular to a substrate (1500). The refractive index periodic structure layer is structured so as to separate a light having a wavelength ? perpendicularly incident on the refractive index periodic structure into at least a transmitted light and a diffracted light. The multilayer mirror is structured so as to have a reflectance with regard to the diffracted light higher than a reflectance with regard to the transmitted light. A resonant mode is realized within a waveguide including the refractive index periodic structure layer and the multilayer mirror.

Abstract: Provided is a two-dimensional surface-emitting laser array that enables to dispose more elements in a smaller area and enables compact size, high resolution, and high speed thereof. The two-dimensional surface-emitting laser array includes surface-emitting laser elements arranged in a two-dimensional manner of m rows and n columns (m is an integer of two or larger, and n is an integer of three or larger). The interval between mesas for arranging electrical wirings for individually driving the surface-emitting laser elements is assigned so that the interval in the m row direction increases according to the number of the electrical wirings passing through between the mesas.