Television – Stereoscopic
Reexamination Certificate
1998-05-29
2003-01-14
Rao, Andy (Department: 2613)
Television
Stereoscopic
C348S043000, C348S046000, C348S047000
Reexamination Certificate
active
06507358
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a multi-lens image pickup apparatus having plural image pickup systems.
2. Related Background Art
In a camera having a single image pickup system and single image display means, the image picked up by the image pickup system is conventionally stored in a video memory (VRAM) provided in the camera. Thereafter the controller of the image display means reads, from the VRAM, the pixel values of the points constituting the image and display the image on the image display means. In such single-eyed camera system, the image picked up by the image pickup system can be simply entered in the VRAM, so that a moving image can also be displayed on the image display means with an image pickup rate same as that for the still image.
On the other hand, as a system for picking up and displaying a stereoscopic image, there is conventionally known, for example, a stereoscopic television apparatus disclosed in the Japanese Patent Laid-open Application No. 62-21396. In such stereoscopic image pickup and displaying system, a set of images having a parallax are basically picked up with plural cameras and are displayed on an exclusive stereoscopic image display device to provide a stereoscopic image to the photographer.
In such stereoscopic image pickup/displaying system, as the cameras for image pickup are separated from the stereoscopic display device for stereoscopic image display, the photographer is unable to constantly observe the stereoscopic image, so that it is difficult to adjust the cameras under the observation of the image.
Also in case of image pickup while the cameras are moved, there are required operations of, at first, picking up the image while the display is detached and then editing the image while the image is displayed, so that the stereoscopic image cannot be picked up in a simple manner.
Also for displaying a stereoscopic image, there is known a method of forming a right-eye image and a left-eye image of different polarized states and separating the left and right images with polarizing spectacles, and, for forming such different polarized state, the display device is provided with a liquid crystal shutter for switching the polarized state in synchronization with the field signal of the displayed image, whereby the observer wearing the polarizing spectacles observes the left and right images with respective eyes, one at a time on time-shared basis, the stereoscopic observation is enabled. This method, however, is associated with a drawback that the observer has to always wear the polarizing spectacles.
On the other hand, for stereoscopic image display without such polarizing spectacles, there is known a method of providing a lenticular lens in front of the display, thereby spatially separating the image entering the left and right eyes.
FIGS. 21A and 21B
show a conventional stereoscopic image display method employing the lenticular lens. Referring to
FIG. 21A
showing a view seen from the top of the observer, there is shown a display pixel unit
60
of a liquid crystal display, of which the glass substrates, color filters, electrodes, polarizing plates, rear light source etc. are omitted. The display pixel unit
60
is composed of apertures
61
constituting pixels and provided with color filters, and a black matrix
62
separating the pixels. The apertures
61
are arranged as shown in FIG.
21
B.
On the surface of the liquid crystal display, there is provided a lenticular lens
63
consisting of cylindrical lenses each having a semicircular cross section and extending in a direction perpendicular to the plane of the drawing, and the display pixel unit
60
of the liquid crystal display is positioned at the focal plane of such lenticular lens. On the display pixel unit
60
, right-eye images (R) and left-eye images (L) of stripe shape are alternately arranged in such a manner that a pair of such images corresponds to a pitch of the lenticular lens
63
, and are optically separated by the lenticular lens
63
to the right eye Er and the left eye El of the observer whereby the stereoscopic observation is rendered possible.
In
FIG. 21A
there are illustrated spatial areas where the right-eye image and the left-eye image can be respectively observed by the cylindrical lens at the central part of the display. For each of other cylindrical lenses, the spatial areas are similarly separated at the left and at the right for the respective eyes of the observer, whereby the left and right images are uniformly separated and observed over the entire image area.
In this method, the horizontal resolving power of the image display device is reduced to 1/2 since the stripe images, synthesized from the two parallax images, have to be displayed.
On the other hand, the Japanese Patent Laid-open Application Nos. 5-107663 and 7-234459 disclose stereoscopic image display devices without loss of the resolving power.
FIGS. 22A
to
22
C illustrate the configuration and the display method of the stereoscopic image display device disclosed in the Japanese Patent Laid-open Application No. 5-107663. This device is composed of a light directionality switching device
72
consisting of a matrix planar light source
70
and a lenticular lens sheet
71
, and a transmissive display device
73
(FIG.
22
A). When stripe-shaped light sources
70
R for the right eye (cf.
FIG. 22B
) are turned on, an image
73
R for the right eye is displayed in synchronization in an odd frame (or field) (cf. FIG.
22
C), and, when stripe-shaped light sources
70
L for the left eye are turned on, an image
73
L for the left eye is displayed in synchronization in an even frame (or field). Since all the pixels are used in each of the even and odd frames (or fields), the pixels need not be split and the horizontal resolving power is not deteriorated.
In the aforementioned conventional example, however, in case of displaying paired images picked up with a multi-lens image pickup apparatus, such paired images cannot be simultaneously written into the VRAM.
In order to overcome such drawback, there is known a method of writing an image into a half area of the VRAM while temporarily retaining the other image in another memory, and, after such image writing into the VRAM, transferring the other image from such memory to the VRAM, thereby displaying the image pair on single image display means. In such method, however, since the image displayed on the image display means is switched, there results a drawback that the display rate becomes slower in comparison with the image pickup rate.
On the other hand, the conventional configuration employing the lenticular lens on the surface of the liquid crystal display is associated with drawbacks that the image quality is deteriorated by the surface reflection from the lenticular lens surface and that the black matrix of the liquid crystal display is observed as moire fringes.
Also in the stereoscopic displaying method by displaying the right-eye image and the left-eye image on time-shared basis, the switching of the images has to be conducted at a high speed in order to prevent the flickering phenomenon.
Isono et al. reported, in ‘Conditions for stereoscopic observation’, Journal of Television Association, Vol. 41, No. 6 (1987), pp549-555, that stereoscopic observation could not be obtained with the time-shared method of a field (frame) frequency of 30 Hz.
Also the limit frequency at which the flickering is not sensed when both eyes are alternately opened and closed (called critical fusion frequency or CFF) is about 55 Hz, indicating that the field (frame) frequency has to be at least 110 Hz in terms of the flickering. Consequently there is required a transmissive display device capable of high-speed display.
Also in such stereoscopic image systems, there has not been considered the compatibility with the two-dimensional image which is dominant in the current image pickup systems. Stated differently, the stereoscopic image system and the two-dimensional image system have been constructed as separate indep
Iijima Katsumi
Kurahashi Sunao
Mori Katsuhiko
Sakimura Takeo
Yano Kotaro
Canon Kabushiki Kaisha
Fitzpatrick ,Cella, Harper & Scinto
Rao Andy
LandOfFree
Multi-lens image pickup apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Multi-lens image pickup apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multi-lens image pickup apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3063472