Abstract: A light source (27) comprises a header (30), electrical conductors (31), (32), (33), a light sensor (40), a laser (39), a can (28), a convex lens (36), and an external control circuit (34). A window (35) is defined in an inclined top of the can (28), and the convex lens (36) is mounted within the window (35). A convex surface of the inclined convex lens (36) faces away from the light sensor (40). The laser (39) and the light sensor (40) are separately mounted on the header (30). The electrical conductors (31), (32), (33) electrically connect with the control circuit (34). The convex lens (36) has a pre-determined curvature such that emitted light beams of the laser (39) reflected from the lens (36) converge onto the light sensor (40). Accordingly, the reflected light beams (52) received by the light sensor (40) are accurately proportional to the emitted light power of the laser (39).

Abstract: The invention relates to compound cavity optical reflection modulation laser system providing frequency modulation of laser light by phase induced effective reflection modulation of the laser rear facet. The system includes a single mode gain coupled DFB laser integrated with a passive waveguide section to form a compound cavity modulation system. The waveguide includes a multiple quantum well region which is reverse biased to utilize the quantum Stark effect for voltage controlled refractive index modulation, thus providing phase modulation of the laser light. The phase modulated light is fed back to the laser to interfere with the light generated within the laser and to form the output light generated from the compound cavity. The interference effects cause modulation of the effective complex reflection of the rear laser facet which results in frequency modulation of the output light.

Abstract: An energy stabilization method and system includes an energy detector and simulating optics before the detector for forming a diagnostic portion of an output beam to simulate the beam profile of the working beam incident at the workpiece. Preferably, the simulating optics before the detector are selected to be identical or similar to beam transforming optics that the working beam traverses after the diagnostic portion is split off from the working beam, but before the working beam reaches the workpiece. The diagnostic beam portion is thus formed to have an identical or similar beam profile as the working beam at the workpiece. Alternatively, instead of providing transforming optics along the diagnostic beam path that are the same or similar to those encountered by the working beam, a processor configures the data received at the detector to simulate the beam profile of the working beam at the workpiece, after it traverses the transforming optics described above.

Abstract: A circuit method for recognizing an interruption in a light waveguide link, wherein the amplified spontaneous emission output by an intensifying fiber is monitored for recognizing an interruption along a light waveguide link having an intensifying fiber and, given failure of the amplified spontaneous emission to arrive, the transmission unit supplying the light signals into the light waveguide link is shut off.

Abstract: A molecular fluorine (F2) laser is provided wherein the gas mixture includes molecular fluorine for generating an emission spectrum including two or three closely spaced lines around 157 nm. An optical method and means are provided for selecting an emission line from among the plurality of closely spaced emission lines of the molecular fluorine laser gas volume and broadening the spectrum of said selected emission line. This approach of broadening the spectrum reduces the coherence length of the output beam. As a result, speckle may be reduced or avoided in microlithography applications.

Abstract: In the method and the arrangement, a ratio (p2/P3)—which is independent of the total optical power of the laser (1)—between a power (p2) essentially containing only the wavelength (&lgr;) to be stabilized, which power is filtered out from a portion (P2) of the total power (P0), and an additional portion (P3) is measured and compared to a desired value (S0), and, given a deviation from the desired value (S0), the temperature of the laser (1) is controlled to the desired value (S0).

Abstract: An apparatus and method for automatically analyzing and controlling intensity of a train of high speed, high power multi-level optical pulses. The invention includes an optical pulse generator for generating the train of high speed, high power, multi-level optical pulses, wherein the optical pulse generator provides a low optical intensity level and a medium optical intensity level and a high optical intensity level. A photodetector is optically coupled with the optical pulse generator for generating a train of electrical pulses having amplitude levels in response to optical intensity levels of the train of optical pulses. At least one reference is employed, wherein an analyzer electrically coupled with the reference and the photodetector for analyzing the amplitude levels of the train of electrical pulses in comparison to the reference. A controller is electrically coupled with analyzer for generating a high correction signal based upon the analysis of the amplitude levels.

Abstract: A laser light intensity controller includes a polarizing beam splitter for passing most of one of an x-direction polarization component perpendicular to a direction in which a laser beam emitted from a light source travels and a y-direction polarization component parallel with the traveling direction and for reflecting a little portion of the one polarization component as monitoring light, and a photodetector for receiving the reflected monitoring light to generate a light intensity signal. The controller drives the light source in accordance with the light intensity signal. The photodetector reflects the other of the x-direction polarization component and the y-direction polarization component and is not sensitive thereto, and absorbs the one polarization component and is sensitive thereto.

Abstract: A laser light intensity controller includes a polarizing beam splitter for passing most of one of an x-direction polarization component perpendicular to a direction in which a laser beam emitted from a light source travels and a y-direction polarization component parallel with the traveling direction and for reflecting a little portion of the one polarization component as monitoring light, and a photodetector for receiving the reflected monitoring light to generate a light intensity signal. The controller drives the light source in accordance with the light intensity signal. An optical element which passes passing only the one polarization component is installed between the light source and the polarizing beam splitter.

Abstract: A laser assembly has at least one optic element (6, 8) in the path of the laser beam (5) and at least partially permeable to the laser beam (5). There is at least one component for detecting the temperature of the optic element (6, 8) or which can detect the intensity of the light beamed by the optic element (6, 8). The laser beam (5) can be controlled to influence the temperature of the optic element (6, 8) depending upon the light intensity detected.

Abstract: An image forming apparatus is arranged to form an image with laser light emitted from a semiconductor laser source, and is constructed so as to protect the laser source from a breakdown, by regulating electric current flowing to the laser source no matter when an adjusting circuit for adjusting the light amount of the semiconductor laser source is apt to supply the electric current that could break the laser source, to the laser source.

Abstract: A multi-beam source unit adjusting method is disclosed wherein an arrangement direction of light emitting points of a multi-beam laser diode relative to a horizontal scanning direction of a scanning optical system can be aligned with a predetermined standard design line direction.

Abstract: A multi-beam source unit is disclosed wherein an arranged direction of light emitting points of a multi-beam laser diode relative to a horizontal scanning direction of a scanning optical system can be aligned with a predetermined standard design line.

Abstract: An optical scanning device is provided with a light source that emits a light beam, a driver that controls output power and modulation of the light beam emitted by the light source, a controller that transmits, to the driver, power control data and modulation data respectively used for controlling the output power and modulation of the light beam. The optical scanning device is further provided with a single data bus that connects the driver and the controller. The power control data and the modulation data being transmitted through the single data bus at different timing.

Abstract: A fiber Bragg grating is used to stabilize the intensity and frequency fluctuations of a diode laser. The diode laser is connected with an opto-mechanical apparatus to the fiber which contains the grating. The grating is formed in the guided-mode region of the optical fiber. The wavelength of maximum grating reflectivity is selected to lie near the maximum of the diode laser gain bandwidth. The magnitude and bandwidth of the grating reflectivity stabilizes the diode laser output without appreciably reducing the optical output power from the end of the fiber. The bandwidth of the optical spectrum of the diode laser is selected depending on the distance of the grating from the diode laser.