Abstract: Backlight units include a light guide plate having a plurality of light extraction features, at least one light source optically coupled to a second major surface of the light guide plate, a rear reflector positioned proximate the second major surface, and a patterned reflective layer positioned proximate a first major surface of the light guide plate. Display and lighting devices comprising such backlight units are further disclosed.

Abstract: Backlight units include a light guide plate having a plurality of light extraction features, at least one light source optically coupled to a second major surface of the light guide plate, a rear reflector positioned proximate the second major surface, and a patterned reflective layer positioned proximate a first major surface of the light guide plate. Display and lighting devices comprising such backlight units are further disclosed.

Abstract: Methods of operating a frequency-converted laser source are disclosed. According to particular disclosed embodiments, a laser diode is driven in a pulsed mode to define pixel intensity values corresponding to desired gray scale values of image pixels in an image plane of the laser source. The pixel intensity values are a function of a laser control signal comprising a discontinuous pulse component, a relatively constant intensity component I, and a continuously variable intensity component I*. The pulse width w of the discontinuous pulse component is selected from a set of discrete available pulse widths according to a desired pixel gray scale value. A low-end pulse width w of the set of available pulse widths is established for a range of low-end pixel gray scale values and progressively larger pulse widths w are established for ranges of progressively higher pixel gray scale values.

Abstract: Methods of operating a frequency-converted laser source are disclosed. According to particular disclosed embodiments, a laser diode is driven in a pulsed mode to define pixel intensity values corresponding to desired gray scale values of image pixels in an image plane of the laser source. The pixel intensity values are a function of a laser control signal comprising a discontinuous pulse component, a relatively constant intensity component I, and a continuously variable intensity component I*. The pulse width w of the discontinuous pulse component is selected from a set of discrete available pulse widths according to a desired pixel gray scale value. A low-end pulse width w of the set of available pulse widths is established for a range of low-end pixel gray scale values and progressively larger pulse widths w are established for ranges of progressively higher pixel gray scale values.

Abstract: The present invention relates generally to semiconductor lasers and laser projection systems. According to one embodiment of the present invention, a projected laser image is generated utilizing an output beam of the semiconductor laser. A gain current control signal is generated by a gain current feedback loop to control the gain section of the semiconductor laser. Wavelength fluctuations of the semiconductor laser are narrowed by incorporating a wavelength recovery operation in a drive current of the semiconductor laser and by initiating the wavelength recovery operations as a function of the gain current control signal or an optical intensity error signal. Additional embodiments are disclosed and claimed.

Abstract: The present invention relates generally to semiconductor lasers and laser projection systems. According to one embodiment of the present invention, a method of correcting output power variations in a semiconductor laser is provided. According to the method, an output power feedback loop is utilized to generate optical intensity feedback signals representing actual output power of the laser source for discrete portions V1, Vi, . . . Vj of the image signal. Error signals E1, Ei, . . . Ej are generated representing the degree to which actual projected output power varies from a target projected output power for the discrete portions V1, Vi, . . . Vj of the image signal. These error signals E1, Ei, . . . Ej are utilized to apply corrected control signals G1?, Gi?, . . . Gj? to the gain section of the semiconductor laser for projection of compatible discrete portions V1?, Vi?, . . . Vj? of the image signal.

Abstract: The present invention relates generally to semiconductor lasers and laser projection systems. According to one embodiment of the present invention, a method of correcting output power variations in a semiconductor laser is provided. According to the method, an output power feedback loop is utilized to generate optical intensity feedback signals representing actual output power of the laser source for discrete portions V1, Vi, . . . Vj of the image signal. Error signals E1, Ei, . . . Ej are generated representing the degree to which actual projected output power varies from a target projected output power for the discrete portions V1, Vi, . . . Vj of the image signal. These error signals E1, Ei, . . . Ej are utilized to apply corrected control signals G1?, Gi?, . . . Gj? to the gain section of the semiconductor laser for projection of compatible discrete portions V1?, Vi?, . . . Vj? of the image signal.

Abstract: Particular embodiments of the present invention relate generally to semiconductor lasers and laser scanning systems and, more particularly, to schemes for controlling semiconductor lasers. According to one embodiment of the present invention, a laser is configured for optical emission of encoded data. At least one parameter of the optical emission is a function of a drive current IGAIN injected into the gain section of the semiconductor laser and one or more additional drive currents I/VPHASE, I/VDBR. Mode selection in the semiconductor laser is altered by perturbing at least one of the additional drive currents I/VPHASE, I/VDBR with a perturbation signal I/VPTRB to alter mode selection in the semiconductor laser such that a plurality of different emission modes are selected in the semiconductor laser over a target emission period.

Abstract: Particular embodiments of the present invention relate generally to semiconductor lasers and laser scanning systems and, more particularly, to schemes for controlling semiconductor lasers. According to one embodiment of the present invention, a laser is configured for optical emission of encoded data. At least one parameter of the optical emission is a function of a drive current IGAIN injected into the gain section of the semiconductor laser and one or more additional drive currents I/VPHASE, I/VDBR. Mode selection in the semiconductor laser is altered by perturbing at least one of the additional drive currents I/VPHASE, I/VDBR with a perturbation signal I/VPTRB to alter mode selection in the semiconductor laser such that a plurality of different emission modes are selected in the semiconductor laser over a target emission period.

Abstract: The present invention relates generally to semiconductor lasers and laser scanning systems and, more particularly, to schemes for controlling wavelength in semiconductor lasers. According to one embodiment of the present invention, a method of minimizing laser wavelength variations in a semiconductor laser is provided. According to the method, one or more of the laser drive currents is configured to comprise a drive portion and a wavelength recovery portion. The wavelength recovery portion of the drive current comprises a recovery amplitude IR that is distinct from the drive amplitude ID and a recovery duration tR that is less than the drive duration tD. The recovery amplitude IR and duration tR are sufficient to recover carrier density distribution distorted by gain compression effects prior to recovery. Additional embodiments are disclosed and claimed.

Abstract: The present invention relates to methods for modulating a semiconductor laser and wavelength matching to a wavelength converter using monolithic micro-heaters integrated in the semiconductor laser. The present invention also relates to wavelength matching and stabilization in laser sources in general, without regard to whether the laser is modulated or whether second harmonic generation is utilized in the laser source. According to one embodiment of the present invention, a method of compensating for thermally induced patterning effects in a semiconductor laser is provided where the laser's heating element driving current IH is set to a relatively high magnitude when the laser's driving current ID is at a relatively low magnitude. Additional embodiments are disclosed and claimed.