Television – Stereoscopic – Picture signal generator
Reexamination Certificate
1998-01-16
2003-06-17
Kelley, Chris (Department: 2613)
Television
Stereoscopic
Picture signal generator
Reexamination Certificate
active
06580448
ABSTRACT:
BACKGROUND OF THE INVENTION
The invention concerns a process for collecting and recording visual information in parallel with an initial stereoscopic sensor system recording optical information, for instance the eyes of a person, and a device for carrying out such a process.
In manual activities which must be carried out extremely accurately, the result depends strongly on accurate observation during the activity. This is particularly the case for surgery on human or animal bodies. If the person operating does not observe the tissue in the vicinity of the knife accurately enough, there is a danger that an important structure such as a nerve bundle will be severed.
In systems with high hazard potential, such as nuclear power plants, assembly and checking must be done very accurately with good visual observation. Accurate observation is also essential in manipulations and tests during space flight, flying, and in complex terrestrial systems.
The desire to make what a person sees recordable is old, and until now it has not been possible to accomplish it. The attempt to obtain image information by sampling from the optic nerve does not take us to that objective because a significant portion of the signal processing and image collection occurs only in the brain.
One or more video monitoring cameras recording the whole area that can be examined by a person only show what is available, but not what the observing person sees. In order to be able to analyze potentially incorrect action of the person, it is certainly convenient if monitoring cameras record all that is visible. In addition, though, it is necessary to determine what is seen by the person observed.
A microscope headpiece which can be worn during surgery is known from U.S. Pat. No. 4,395,731. The operating field is monitored by two video camera placed in front of the eyes. The images from the video cameras are sent to monitors or image areas immediately in front of the eyes. Use of zoom optics makes it possible to magnify segments of the operating field.
The eyes always remain directed to the image source (e. g., a CRT). That can quickly lead to fatigue. It is also impossible to determine how the eyes comprehend the image provided to them. It could be that an important image area in the image source is never realized as such unless it falls on the portion of the retina that allows sharp vision. The focusing and alignment of the two cameras fixes the distance required between the cameras and the surgical field in order to get a sharp view with proper perspective. If this distance changes because of head movements, the images shown on the monitors can be unsharp, and/or may not be viewed by the eyes in such a way as to give a three-dimensional image. The ability for manual adjustment is hardly suitable for matching the orientation of the cameras to short-term changes in distance. Another disadvantage of the microscope headpiece is the limitation of the field of view by the camera optics and by the limited size of the monitors. Furthermore, changes in the field of view through movement of the eyes on the image area of the cameras or monitors are limited. An optical system which attempts to determine the observations of the operating or controlling person in which the person sees only the images from the cameras severely limits the ability of this person to observe and does not show what areas of the images provided are being looked at.
SUMMARY OF THE INVENTION
The objective of the invention is to determine what image information is actually seen by a person, or by any light-sensitive sensor system.
The solution according to the invention provides an image-recording control system, itself known from U.S. Pat. No. 5,341,181, acting in parallel with the eyes of the person or in parallel with a light-sensitive sensor system, the information record of which is made to coincide at least approximately such that at least one optical parameter of the eyes of or the image-recording initial system is determined and the corresponding optical parameter of the control system is adjusted in dependence on it. However, as the known system from the U.S. Patent is limited to a single control system which does not operate stereoscopically, the optogeometric determination of the image seen is only approximate. In contrast, according to the invention, an optical system is used which determines the stereo base (generally the interpupillary distance) and uses the directions of the fixation lines of the eyes to determine the fixation point. If the fixation point is known, the parallel observation of the working or controlling person is accomplished more accurately than in the system according to U.S. Pat. No. 5,341,181. Each new eye position is determined. The optical axes are preferably determined in a coordinate system which is fixed in relation to the head and which therefore moves with the head. As the movements of each eye are produced by six external eye muscles, it is possible to provide a sensor means which determines the stimuli to these muscles and derives from those the current eye position or the optical axes of the eyes.
Now the eye positions, or the directions of the visual axes, which are known in a coordinate system linked to the head, are used to control the directions of at least one, but preferably two cameras, through a mount connected with the head. The at least one camera is then connected with the head so that it can, like the eyes, carry out not only movements due to head movements but also movements relative to the head. It is apparent that an adjustable optical imaging system, especially one with adjustable mirrors or the like, can be provided to adjust the solid angle region being imaged in place of camera movement. Potential applications arise from quite different areas. One such area is that of video telephony, in which one of the speakers can observe the same thing, to a certain extent, with the eyes of the user, without added technical recording manipulations being required. In one preferred embodiment, cameras with CCDs are placed at the temple areas at both sides of the head. Each camera is assigned to the nearer eye. A mounting system, in particular, a kind of gimbal mount which makes camera movements possible is provided on a holder part which can be placed on the head, and an actuating means is provided. A camera, or its optical axis, is moved, for instance, by the movement of a rod which runs parallel with the camera axis and is connected to the camera. The rod is moved in a plane orthogonal to the rod by means of two linear drives arranged essentially perpendicularly to the rod.
As the camera positions are somewhat displaced from the eye positions, a geometric correction must be taken into consideration for control of the camera direction. This correction should assure that the two camera axes intersect at the same point as the intersection of the two visual axes of the eyes. No correction is needed for parallel visual axes.
In order to determine the fixation point of the eyes, it must be taken into consideration that the line of fixation of the eye does not coincide with the optical axis. The optical axis of the eye is the axis that is essentially symmetrical in rotation with respect to the optical structure of the eye (cornea, iris, lens). But because the most sensitive region of the retina, the
Fovea centralis
, is somewhat to the side of that axis, the line of sight or line of fixation is angled somewhat with respect to the optical axis. The deviation between these two lines can be considered as a standard difference, or it can be determined by fixing the eyes on a point of known position with a specified head orientation, and then measuring the directions of the visual axes of the eyes. From the known head direction, or the positions of the eyes and of the specified point of fixation, fixation lines are constructed so that the deviations between the visual axes and the corresponding fixation lines can be determined.
On consideration of the different directions of the visual axes and the line of sight of an
Hodgson & Russ LLP
Kelley Chris
Leica Microsystems AG
Vo Tung
LandOfFree
Process and device for the parallel capture of visual... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process and device for the parallel capture of visual..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process and device for the parallel capture of visual... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3139775