Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Tomo Kishigami

Nobuo Takeshita

Yoshihiro Kiyose

Osamu Tsukahara

Hironori Nakahara

Yusuke Kanatake

Toshiya Matozaki

Nozomi Nakagawa

Masaharu Ogawa

Toru Yoshihara

Atsushi Michimori

Shota Nakahara

Koichi Ikuta

A display device used in a vehicle for displaying virtual images includes: a display including a light source to emit image light and a screen on which the image light is projected; and a controller to adjust positions at which the virtual images are displayed. Images displayed on the screen are projected as the virtual images. The virtual images include first and second virtual images displayed at different positions. The display displays, on the screen, a first adjustment image that is projected to a display area of the first virtual image and a second adjustment image that is projected to a display area of the second virtual image. The controller adjusts a position of the display area of the first virtual image and a position of the display area of the second virtual image on a basis of the first adjustment image and the second adjustment image.

Display device and adjustment method

An image display apparatus includes: a light source unit including three or more light sources, combining lights from the light sources and emitting the combined light; a wavelength detector that detects, for each light source, wavelength information indicating the wavelength of light from the light source; a color value determiner that determines, for each light source, from the wavelength information, a color value indicating a color of light from the light source in a predetermined color space; a correction value determiner that determines, based on the color values, a correction value for correcting a ratio between the intensities of lights from the light sources so that the color of the combined light is a color to be displayed; and a driver that drives the light sources so that the ratio between the intensities of lights from the light sources is a ratio corrected based on the correction value.

Image display apparatus and display correction method

A virtual image display device includes a light source unit, a polarization switching unit, an image generation unit, an optical path unit and a projection unit. The polarization switching unit switches a polarization direction of a light beam emitted from the light source unit. The optical path unit includes a first optical path through which the light beam having the first polarization direction travels and a second optical path through which the light beam having the second polarization direction travels. A first virtual image is displayed at a first distance with the light beam that has traveled through the first optical path. A second virtual image is displayed at a second distance farther than the first distance with the light beam that has traveled through the second optical path.

Virtual image display device

The image display device () provides images perceivable from the area of the eye box (E), and includes a light source unit (), a screen (), a scanning unit () and an optical system (). The screen () has a single micro lens array () on which multiple micro lenses () are arranged. The scanning unit () includes a mirror () to reflect beams emitted from the light source unit (), and swings the mirror () around a pivot center () to scan the beams thereover, thereby generating images. The optical system () brings the images formed on the screen () to the eye box (E). An angle (&#x3b8;) formed between a zero-order diffracted beam and a first-order diffracted beam, which are among a luminous flux of beams diffracted by the screen () and pass through the center of the eye box (E), is smaller than a minimum visual angle (V).

Image display device

An image projection apparatus () joins a plurality of display images displayed by scanning a plurality of light beams, as if there is no seam between them, thereby displaying a large-sized high-quality image. The image projection apparatus () includes a MEMS mirror device (), a MEMS mirror control unit (), and a laser beam detector (). The MEMS mirror control unit () makes the laser beam detector () irradiated with a first light beam (L), and at this time adjusts a position of a first display image () on the basis of a difference between a detection signal output from a first light sensor () and a detection signal output from a second light sensor (); the MEMS mirror control unit () makes a first light reception surface and a second light reception surface irradiated with a second light beam (L), and at this time adjusts a position of a second display image () on the basis of a difference between a detection signal output from the first light sensor () and a detection signal output from the second light sensor ().

Image projection apparatus

A laser scanning device includes: a plurality of laser light sources, each of the plurality of laser light sources emitting a laser light having a light intensity distribution having an elliptical shape; an aperture through which the laser lights emitted from the plurality of laser light sources pass; and a scanning mirror for reflecting the laser lights from the aperture to a scan position. A position of the aperture is adjustable in a first adjustment direction. The plurality of laser light sources are oriented so that long axis directions of the light intensity distributions of the laser lights emitted by the plurality of laser light sources are parallel to the first adjustment direction at positions at which the laser lights emitted by the plurality of laser light sources enter the aperture.

Laser scanning device

An optical information processing apparatus includes: a unit that radiates light onto an optical disc and detects the reflected light to output a reproduced signal; a unit that corrects spherical aberration of the light; a unit that adjusts a focus position of the light based on a focus adjustment value; and an adjustment unit that measures a characteristic of the reproduced signal at each of at least three positions on each of at least three straight lines on a plane with coordinate axes representing an amount of spherical aberration correction and focus adjustment value, obtains, from the measurements, as estimated positions, at least five positions on the plane at which the characteristic has substantially the same value, performs an ellipse approximation on the estimated positions, obtains a center of the ellipse, and determines the amount of spherical aberration correction and focus adjustment value based on the center of the ellipse.

Optical information processing apparatus and optical information processing method, and adjustment device, adjustment method, and adjustment program for optical information processing apparatus

In an optical recording method, recording parameters (WU) to be used for recording are obtained using recommended recording parameter values (WR) read from an optical recording medium and previously obtained vector information (PC) and approximation coefficients (Ca, Cb) (S). Writing to the optical recording medium is performed using the obtained recording parameters (S). The vector information (PC) includes a vector component of the parameters obtained statistically with respect to parameter difference values (DF) between optimal recording parameter values (WO) and the recommended recording parameter values (WR) over a plurality of optical recording media so as to strengthen mutual correlation between the parameters. The approximation coefficients (Ca, Cb) are obtained by approximating a relationship between converted information (X) and feature information (D), the converted information (X) indicating a relationship between the vector information (PC) and the parameter difference values (DF), the feature information (D) indicating the features of each optical recording medium obtained from the recommended recording parameter values (WR) and the vector information (PC).

Optical recording method and optical recording device

An optical information processing method and apparatus performs a light irradiating and receiving step, a signal processing step, and an adjusting step of a spherical aberration and a focus offset on the basis of shift amount of first and second control devices and a performance evaluation value. The performance evaluation values for first, second, third and fourth points in an x and y coordinate system are detected, in which an x-coordinate is one of the shift amount of the first control device and the shift amount of the second control device and a y-coordinate is the other, the first point, second and third points having the same y-coordinate and different x-coordinates with each other, the fourth point being provided on a first straight line passing through the first point and being different from the first point.

Optical information processing method and optical information processing apparatus

A recorded area is reproduced during a suspension of a recording operation; when degradation of the recorded signal is detected (S, S) by the signal quality detection means (), a tilt adjustment is performed in the recorded area, the signal quality of the recorded signal is detected after the tilt adjustment (S), and if it is still degraded, a recording parameter is altered (step S). The need to obtain tilt adjustment values for tilt corrections at a plurality of radial positions in advance is eliminated, resulting in reduced apparatus overhead and better recording quality.

Optical disc apparatus and recording method

An optical recording/reproduction method and device that can perform control for optimizing the amount of spherical aberration in a multilayered optical disc in a short period of time. When the objective lens is displaced in the focusing direction, the amplitude value of the focusing error signal detected just after leaving the focal position of a given first recording layer and the amplitude value of the focusing error signal detected just before passing through the focal position of a given second recording layer other than the first recording layer are measured with a particular spherical aberration, the amplitude ratio of amplitude values is calculated, the difference between spherical aberration and the optimal spherical aberration for the second recording layer is approximated as a function of the amplitude ratio, the optimal spherical aberration is calculated on the basis of this approximation, and the spherical aberration is set.

Optical recording/reproduction method and optical recording/reproduction device

According to a method for setting the laser beam power applied to reproduce information recorded on an optical disc, information recorded in a region on the optical disc is reproduced using three or more test reproduction powers (SB), the number of reproductions until the degradation of the quality of the reproduced signal reaches a prescribed value is determined as the degradation number of reproductions (SF), the relation between the test reproduction power and the degradation number of reproductions is approximated by a curve, and a reproduction power restricting the degradation of the reproduced signal quality to a predetermined amount or less over a certain guaranteed number of reproductions is determined (SF). In optical reproduction from an optical disc on which information is recorded, the optimum power of irradiation for reproduction can be set, and degradation of the information due to the reproducing light can be prevented.

Optical disc reproduction power setting method, optical disc reproduction method, and optical disc device

In a medium of the phase change type, a power ratio and modulation degree for use in recording are determined from a recommended pulse width value in the recommended write strategy parameters recorded in the optical disk, the recommended power ratio value, the recommended recording power value, and the characteristics of the optical recording device, and recording is carried out on the optical disk according to the power ratio value and modulation degree value thus determined. Optimal recording can be carried out even on an optical disk for which the optimal write strategy information has not been determined in advance, without the need to store write strategy information suitable for each and every optical disk.

Before new information is recorded on a comparatively deep recording layer in a multilayer optical recording disc, a predetermined target value of a reproduced signal parameter is read from the disc itself or from a separate storage unit, the recorded/unrecorded states of the shallower recording layers are determined, and the target value is corrected on the basis of these states. The correction is based on a predetermined difference in the value of the reproduced signal parameter caused by a difference in the recorded/unrecorded states of the shallower recording layers. The corrected target value is used in calibration of the recording power by means of a test write. This correction of the target value permits reliable recording on a multilayer optical disc without delaying the start of the recording process.

Optical recording device and method

In a recording method for recording information on an optical recording medium () according to the parameters of a write strategy by repeatedly recording (S) a certain amount of information onto the optical disc () and entering a standby state (S) in which recording is suspended and data are stored in a buffer memory (), during an interval while recording is suspended, the information recorded just before is reproduced, the quality of the reproduced signal is measured (SA), and the write strategy is altered as necessary (SC) to obtain consistent recording quality. Only one correction is made per suspension period. Consistent recording quality is thus obtained despite changes in the recording position on the optical disc or changes in recording conditions.

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Tokyo, Japan

Tomo Kishigami