摘要:
A laser projector includes a green laser, a two-wavelength laser, a PBS, a collimator lens, a two-axis galvanometer mirror, a group of lenses, and a screen. The green laser emits a green laser beam. The two-wavelength laser emits red and blue laser beams. The PBS is provided at the position where respective optical paths of laser beams emitted from respective lasers cross each other to cause these optical paths to coincide with each other.
摘要:
A laser projector includes a green laser, a two-wavelength laser, a PBS, a collimator lens, a two-axis galvanometer mirror, a group of lenses, and a screen. The green laser emits a green laser beam. The two-wavelength laser emits red and blue laser beams. The PBS is provided at the position where respective optical paths of laser beams emitted from respective lasers cross each other to cause these optical paths to coincide with each other.
摘要:
A deviation of an optic axis of a laser projector is detected, and the deviation is corrected. Laser projector's CPU executes: commanding a laser beam source of one color, out of laser beam sources of three colors, to emit a laser beam; shutting off the laser when sensing that the laser beam is received in a light-receiving region; applying a laser of a color to be detected as to the presence or absence of a deviation of the axis until its reception in the light-receiving region is sensed; keeping time starting when light reception in the light-receiving region is sensed and ending when light reception in a light-receiving region adjacent thereto is sensed; calculating a relative time difference of each of the colors with respect to a reference color; and correcting a light emission timing of the laser beam source of each of the color, based on the calculated time.
摘要:
An image display apparatus wherein reduction in contrast or resolution is prevented is provided. A laser projector as an embodiment of the image display apparatus includes a memory storing a threshold value predetermined for changing a driving mode of a laser light source, a calculator for calculating an optical power level for projecting an image, a driving-mode selector selecting a mode for driving the laser light source, a driving controller for sending a signal to the laser light source in accordance with a selected driving mode, and a laser emitter. The laser projector operates at least at a bias current value Ib or more. In this case, when the optical power level is lower than or equal to a predetermined threshold value TH, the laser projector emits pulsed light. When the optical power level based on a video signal exceeds threshold value TH, the laser projector changes the driving mode of laser light emission from pulsed light emission to DC light emission, to supply a current higher than or equal to bias current value Ib to each laser light source.
摘要:
To prevent effectively the flickering of an image due to the switching of a polarization direction while reducing speckle noise. A polarization switching unit is provided in an optical path of laser light to a projection surface A and periodically switches a polarization direction of the laser light emitted therefrom between p and S polarization. A laser control unit controls laser light sources in synchronization with the switching by the polarization switching unit and determines a driving current corresponding to a grayscale to be displayed on the basis of driving current characteristics for P polarization when the polarization direction of the laser light is the P polarization. In addition, the laser control unit determines the driving current corresponding to the grayscale to be displayed on the basis of the driving current characteristics for P polarization when the polarization direction of the laser light is the S polarization.
摘要:
To prevent effectively the flickering of an image due to the switching of a polarization direction while reducing speckle noise. A polarization switching unit is provided in an optical path of laser light to a projection surface A and periodically switches a polarization direction of the laser light emitted therefrom between p and S polarization. A laser control unit controls laser light sources in synchronization with the switching by the polarization switching unit and determines a driving current corresponding to a grayscale to be displayed on the basis of driving current characteristics for P polarization when the polarization direction of the laser light is the P polarization. In addition, the laser control unit determines the driving current corresponding to the grayscale to be displayed on the basis of the driving current characteristics for P polarization when the polarization direction of the laser light is the S polarization.
摘要:
This display includes a control portion controlling a laser beam generation portion to output a first laser beam including a region of relaxation oscillation to a partial first image forming element included in a plurality of image forming elements and to output a second laser beam including no region of relaxation oscillation to a second image forming element, other than the first image forming element, included in the plurality of image forming elements.
摘要:
A laser driver circuit comprising a current supply circuit for supplying a laser diode with a current is provided. The current supply circuit comprises a voltage-to-current converter circuit, a current output line for outputting the current generated by the voltage-to-current converter circuit, a current supply line connected to the laser diode, a ground line connected to the ground, and a current path switch for selectively connecting either the current supply line or the ground line to the current output line. The laser driver circuit further comprises a current output prevention circuit for preventing the voltage-to-current converter circuit from generating the current by disconnecting the voltage input line using a voltage input switch so that the voltage is not input to the voltage-to-current converter circuit, when the current output line and the ground line are connected by the current path switch.
摘要:
A laser driver circuit comprising a current supply circuit for supplying a laser diode with a current is provided. The current supply circuit comprises a voltage-to-current converter circuit, a current output line for outputting the current generated by the voltage-to-current converter circuit, a current supply line connected to the laser diode, a ground line connected to the ground, and a current path switch for selectively connecting either the current supply line or the ground line to the current output line. The laser driver circuit further comprises a current output prevention circuit for preventing the voltage-to-current converter circuit from generating the current by disconnecting the voltage input line using a voltage input switch so that the voltage is not input to the voltage-to-current converter circuit, when the current output line and the ground line are connected by the current path switch.
摘要:
Disclosed is a display device capable of inhibiting a projected picture from occurrence of brightness unevenness while reducing speckle noise. The display device (100) includes a control portion (15) continuously supplying current to a laser beam generation portion (12, 13, 14) nonstop for a period longer than a first period thereby controlling the laser beam generation portion to output the laser beam and controlling the laser beam generation portion to stop the output of the laser beam at least once in a second period scanning one image forming element (1, 2).