Computer graphics processing and selective visual display system – Plural display systems
Reexamination Certificate
1998-06-24
2002-01-15
Hjerpe, Richard (Department: 2774)
Computer graphics processing and selective visual display system
Plural display systems
C345S002100, C345S003100, C345S087000, C345S088000, C345S098000, C345S100000, C345S102000
Reexamination Certificate
active
06339411
ABSTRACT:
DESCRIPTION OF THE RELATED ART
Head-mounted displays comprising display devices such as small liquid crystal display panels disposed inside a casing having the form of a pair of spectacles have been developed, and by wearing one of these head-mounted displays a user can enjoy virtual large-screen video. An example of a known optical system of a head-mounted display is shown in FIG.
1
.
This
FIG. 1
schematically shows an optical system from inside a head-mounted display as seen from the left side (from the side of the left ear of a user wearing the head-mounted display like spectacles); the left-right direction in the figure is the front-rear direction of the head-mounted display, which is positioned in front of the eyes of the user. The optical system includes a back light
71
and a liquid crystal panel
80
disposed horizontally at the top of the head-mounted display. The liquid crystal panel
80
has a display region
81
and an area occupied by a display driving circuit
82
for driving this display region
81
.
Light of a video picture displayed by the liquid crystal panel
80
is reflected by a half mirror
72
onto a concave half mirror
73
, and light reflected and enlarged by this concave half mirror
73
then passes through the half mirror
72
to the eyes of the user. A liquid crystal shutter
74
is disposed in front of the concave half mirror
73
, and by switching this liquid crystal shutter
74
between a transparent state and a blocking state with respect to light from outside the user can as desired control between seeing to the outside through the head-mounted display while still wearing the head-mounted display (that is, seeing the scene outside together with the displayed picture) or seeing only the displayed picture.
SUMMARY OF THE INVENTION
If the display region
81
of the liquid crystal panel
80
has n×m pixels in the horizontal and vertical directions respectively, a dot scan shift register as a pixel driving circuit for driving n pixels arrayed in the horizontal direction and a line scan shift register for sequentially scanning m lines arrayed in the vertical direction are provided in the display driving circuit
82
.
FIG. 2B
is an enlarged view of a part enclosed by the dashed circle in FIG.
2
A and shows parts of the display region
81
and the display driving circuit
82
.
If the liquid crystal panel
80
is a color panel then image data for each of the three colors R, G and B are supplied to it, and
FIG. 2B
shows the construction of a part corresponding to for example R image data in an example wherein as R image data three data are supplied to dot scan shift registers
82
b
,
82
c
and
82
d
in parallel. For example three consecutive data are inputted in parallel for reasons relating to image data transfer speed (dot clock frequency), shift register transfer speed, liquid crystal response speed and resolution and so on. Thus this case of three data parallel input is merely an example, and parallel inputting of four or more data or serial inputting with a single dot scan shift register are also conceivable.
These dot scan shift registers (
82
b
,
82
c
,
82
d
) are provided for data of each of the colors R, G and B, and consequently the area of the circuit part occupied by the dot scan shift registers disposed in the horizontal direction above or below the display region
81
is relatively large. Although only R pixels are shown in
FIG. 2B
as the pixels of the display region
81
, G pixels and B pixels are also similarly arrayed (in substantially the same positions) and driven by a dot scan shift register for G pixels and a dot scan shift register for B pixels.
A line scan shift register
82
a
is disposed as a driving circuit for vertical scanning on the left side or the right side of the display region
81
. This line scan shift register
82
a
is used commonly for all the pixels of the colors R, G and B. That is, the line scan shift register
82
a
executes scanning wherein it successively activates one line of pixels at a time on the basis of a scanning signal generated from vertical and horizontal synchronizing signals, and the signal lines of these lines (pixel gate lines) are common to all the R, G and B pixels of each line.
The display driving circuit
82
thus made up of the dot scan shift registers
82
b
through
82
d
and the line scan shift register
82
a
necessitates a large area for circuit provision on the dot scan shift register side, i.e. in the vertical direction of the display region. That is, although only one single line scan shift register common to R, G and B is needed, because a dot scan shift register must be provided for each of the colors R, G and B at least three are necessary, and in the case of three data parallel inputting shown in
FIG. 2B
nine are necessary.
Here, in the head-mounted display described above, considering the need to make the display part positioned in front of the eyes of the user small and light and considering aesthetic design aspects, it is desirable for the head-mounted display to be made small in the front-rear direction.
To make the head-mounted display small in the front-rear direction, as can be seen from
FIG. 1
it is necessary to reduce the front-rear direction dimensions of the back light
71
and the liquid crystal panel
80
, which are disposed horizontally. However, although reducing the size of the back light
71
is not so difficult, reducing the size of the liquid crystal panel
80
in the front-rear direction (that is, the vertical direction of the screen as seen by the user) is difficult.
This will now be explained with reference to FIG.
2
A. As mentioned above, for the dot scan shift registers to be disposed above or below the display region
81
, the display driving circuit
82
requires a large area for example above the display region
81
, as shown in FIG.
2
A. Consequently, even if the size of the display region
81
is reduced as shown in
FIG. 2A
to reduce the front-rear direction size of the liquid crystal panel
80
, because the size of the display driving circuit
82
in the vertical direction does not change, the front-rear direction size of the liquid crystal panel
80
cannot be effectively reduced.
Although it is conceivable to dispose the dot scan shift registers in a position on the left or on the right of the display region
81
, because in this case the laying of signal lines to the many pixels lined up in the horizontal direction becomes extremely complicated and in the end also necessitates area in the vertical direction, it is not suitable means for solving the problem.
Thus because of the difficulty of reducing the size of the liquid crystal panel
80
in the vertical direction there has been the problem that it is not possible to realize size reduction of a head-mounted display in the front-rear direction.
It is therefore an object of the present invention to provide a display device with which it is possible to effectively realize size reduction in the vertical direction.
To achieve this and other objects, according to a first provision of the invention a display device comprises displaying means for, by having a line scan driving circuit disposed with respect to pixel rows of a horizontal direction of a display region and a pixel driving circuit (dot scan driving circuit) disposed with respect to pixel rows of a vertical direction of the display region, performing image display with pixel groups each forming one line in the vertical direction being scanned in the horizontal direction, vertical-horizontal converting means for converting an image data stream supplied presupposing n pixels in a horizontal direction and m horizontal lines in a vertical scanning direction into an image data stream for m pixels in a vertical direction and n vertical lines in a horizontal scanning direction, and display controlling circuit means for executing image display in the display region of the displaying means by carrying out predetermined processing on and supplying to the pixel driving circuit of the displaying means image data outputted fro
Miyazaki Kazumasa
Nito Keiichi
Shirochi Yoshiki
Takahashi Takao
Toriduka Masami
Hjerpe Richard
Lesperance Jean
Maioli Jay H.
Sony Corporation
LandOfFree
Display device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Display device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Display device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2835624