摘要:
A light emitting apparatus having a surface emitting laser (120) including a substrate (100), a first reflection layer (122), an active layer (123) and a second reflection layer (127) stacked successively on the substrate (100), first and second electrodes (110, 130) formed respectively on the lower surface of the substrate (100) and a portion of the upper surface of the second reflective layer (127), to emit light in the direction of the stacked layers, and a monitoring photodetector (150) stacked on the second reflection layer (127) so as to detect the amount of the emitted light from the surface emitting laser (120), is provided. The monitoring photodetector (150) includes first semiconductor material layer (151), an absorbing layer (157) and second semiconductor material layer (158) stacked successively on the second reflection layer, a third electrode formed on the second semiconductor layer to output detecting signals of the monitoring photodetector (150), and a controlling layer (152) formed on the bottom of the absorbing layer (157) and which intercepts some of the incident light.
摘要:
An integrated laser-based light source (300, 320, 340, 350, 500), which generates an output light beam (119) having a controlled intensity, comprises a light sensor (111, 351), a laser (101), a convex beam-splitting surface (345, 545), and a package (105, 501) that includes a header (103). The light sensor generates an electrical signal representing an intensity of light energy falling on it, and is mounted on the header. The laser has one and only one light-emitting face (109) from which a light beam is radiated as a radiated light beam (107). The laser is mounted in the package adjacent the light sensor with the light-emitting face substantially parallel to the light-receiving face of the light sensor. The convex beam-splitting surface reflects a fraction of the radiated light beam towards the light sensor as a reflected light beam, and transmits the remainder of the radiated light beam as the output light beam. The convex beam-splitting surface is supported in the radiated light beam by the package.
摘要:
An integrated laser-based light source (100,100A-100C,200,250,300,320,340,350,500,600,620,700,720,800,900), which generates an output light beam (119,819) having a controlled intensity, comprises a package (105) in which are mounted a laser (101, 801), a light sensor (111, 811) and a coupler (114, 314A-314D, 514, 614, 714, 814, 914). The laser has one and only one light-emitting face (e.g., 109) from which a light beam is radiated as a radiated light beam (107). The light sensor generates an electrical signal representing the intensity of light energy falling it. The coupler couples a fraction (117, 717, 917) of the radiated light beam to the light sensor, and provides the remainder of the radiated light beam as the output light beam. Since the light coupled to the light sensor by the coupler is a fraction of the radiated light beam, the electrical signal generated by the light sensor also represents the intensities of the radiated light beam and of the output light beam. A suitable control circuit (127, 827), when fed with the electrical signal generated by the light sensor, can control the laser current to hold the electrical signal generated by the light sensor to a predetermined value that corresponds to the output light beam having a predetermined intensity.
摘要:
An integrated laser-based light source (300, 320, 340, 350, 500), which generates an output light beam (119) having a controlled intensity, comprises a light sensor (111, 351), a laser (101), a convex beam-splitting surface (345, 545), and a package (105, 501) that includes a header (103). The light sensor generates an electrical signal representing an intensity of light energy falling on it, and is mounted on the header. The laser has one and only one light-emitting face (109) from which a light beam is radiated as a radiated light beam (107). The laser is mounted in the package adjacent the light sensor with the light-emitting face substantially parallel to the light-receiving face of the light sensor. The convex beam-splitting surface reflects a fraction of the radiated light beam towards the light sensor as a reflected light beam, and transmits the remainder of the radiated light beam as the output light beam. The convex beam-splitting surface is supported in the radiated light beam by the package.
摘要:
In an optical head, a light emitting element emits an optical beam, and the beam is condensed by a condensing element onto an information recording medium. A first plate beam-splitting element has a splitting ratio of P polarization to S polarization, and it splits at least a part of the beam reflected by the information recording medium along a direction different from that of a direction returning to the light emitting element. A second plate beam-splitting element is provided in parallel to the first plate beam-splitting element, and it splits the beam split by the first plate beam-splitting element into at least two beams having polarization planes perpendicular to each other. The two beams are detected by a pair of photosensors. Because the first and second beam-splitting elements are set in parallel to each other, an optical path from the light emitting element to the information recording medium is separated from that of a reflected beam from the medium with a very small angle, and the optical elements can be located at adjacent positions to each other. Thus, the optical head can be made compact to a large extent. Further, the optical head can be sealed for high reliability.
摘要:
A method is described for forming patterns in deposited overlayers on GaAs and for aligning the formed patterns with etch features produced through dry processing. The deposited overlayers on GaAs are protected during pattern formation and subsequent processing by a durable, process integrable mask of hydrogenated amorphous carbon.
摘要:
Bei obigen Einrichtungen ist eine genaue Justierung sehr wichtig; die Einrichtungen sollten jedoch sehr kompakt sein. Es genügt nicht, die Silizium-Ätztechnik für die Genauigkeit auszunutzen. Das optische Sendeelement (LD) befindet sich auf einem ersten Träger (T1), das optische Empfangselement (PD) und die Übertragungsfaser (Fa) auf einem dritten Träger. Dazwischen ist ein zweiter Träger (T2) vorgesehen, der für die Wellenlänge des vom Sendeelement (LD) ausgesendeten Lichts durchlässig ist. Die Träger sind durch anisotropes Ätzen strukturiert, um die Aufnahme der einzelnen Komponenten zu ermöglichen. Außerdem liegen die Träger flach aufeinander und können so justiert werden. Eine Monitordiode (MD) ist vorgesehen. Anwendung der Anordnung in allen Übertragungssystemen mit Lichtwellenleitern.
摘要:
Within a monolithic semiconductor structure (100), passive waveguides (98) couple co-axially offset generation waveguides (94) for generating light waves to mirrors. The passive waveguides (98) can also couple detecting regions (96; Fig. 10) for measuring the light intensity within the laser cavity and adjustable absorption regions (126; Fig. 11) for tuning the wavelength (λ₁-λ₄) of the lightwaves generated by the generation waveguides (94).