Section writing method for volumetric 3D displays

Abstract

This invention describes a data writing method for improving resolution of volumetric 3D display based on a rotating display screen or a rotating display panel. The method separates the active display area of an SLM (or a rotating display panel) into a number of sections. When displayed, each section corresponds to a different volumetric zone in the display space. The display space thereby has a number of zones. The portion of a volumetric 3D image within each zone will therefore be formed by images frames projected from a corresponding section. The image frames from a section is thereby called section frames. The locations of zones are arranged according to their distances with respect to the axis of rotation of the display plane. Inner zones are closer to the axis and outer zones are farther away from the axis. The method writes data to the sections one section at a time in a repetitive and periodical sequence. The images in the sections are displayed in a corresponding sequence, which is also repetitive and periodical. The writing sequence writes more often to the outer sections and less often to the inner sections. Therefore, more section frames are distributed to the outer zones and less section frames are distributed to inner zones. As a result, the distance between adjacent section frames can be maintained roughly even in the display space, regardless of the distance to the axis of rotation of the display plane.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 10 illustrates a volumetric 3D display based on a rotating screen with an optical interfacing unit in the prior arts.

FIG. 11 illustrates an example of optical interfacing unit in the prior arts.

FIGS. 1 a-c illustrates a first example of arrangement of sections on a single SLM panel according to this invention.

FIG. 2 illustrates the arrangement of display zones in the display volume according to section arrangement by FIG. 1.

FIGS. 3 a-c illustrates a first example of a “regular” data writing sequence, the corresponding image display sequence and the resulted frame distribution structure in the prior arts.

FIGS. 3 d-f illustrates a first example of a preferred data writing sequence, its corresponding image display sequence and the resulted frame distribution structure with improved resolution according to this invention.

FIGS. 4 a-b illustrates a second example of a “regular” data writing sequence and the resulted frame distribution structure.

FIGS. 4 c-e illustrates a second example of a preferred data writing sequence, its corresponding image display sequence and the resulted frame distribution structure with improved resolution according to this invention.

FIG. 5 illustrates a second example of arrangement of sections on a single SLM panel and the mapping between sections and display zones according to this invention.

FIGS. 6 a-d illustrates a method of modifying the aspect ratio of a projected sub-frame.

FIGS. 7 a-b illustrates an example of optical setup for the modification method of FIGS. 6a-d.

FIG. 8 illustrates a third example of arrangement of sections on a single SLM panel according to this invention.

FIGS. 9 a-d illustrates an example of arrangement of sections on a moving display panel according to this invention, also showing the effect of a separate display command.

Claims

1. Method for providing a generally uniform frame distribution structure for a volumetric 3D display, said volumetric 3D display comprising a rotating display plane, said display plane rotating around an axis and sweeping a display volume, said display plane comprising a display panel or a media with images projected from a spatial light modulator, said method including the steps of: (1) dividing the display volume into a number of zones according to distance to said axis, zones closer to said axis being inner zones, zones farther away from said axis being outer zones;(2) defining on the display area of said display panel or said spatial light modulator a number of sections, each said section corresponding to one of said zones respectively, sections corresponding to inner zones being inner sections and sections corresponding to outer zones being outer sections;(3) writing image data to be displayed to said sections one section at a time in a repetitive and periodical writing sequence, said writing sequence writing more often to said outer sections and less often to said inner sections;(4) concurrently with step (3), displaying images of said sections in a display sequence corresponding to said writing sequence.

2. Method of claim 1, said display volume being divided into 3 zones, and said display panel or spatial light modulator being defined with 3 sections;said display panel or spatial light modulator comprising the capacity to allow: (1) data writing from the top of the display panel down or from the bottom of the display panel up, and(2) stopping data writing at end of any section and then starting writing from top or bottom of the display panel.

3. Method of claim 2, said 3 sections comprising: section-1 in the top area of the display panel, section-2 in the middle area of the display panel and section-3 in the bottom area of the display panel;said writing sequence comprising the following order of data writing to said 3 sections: section-1, section-2, section-3, section-1, section-3, section-1,section-3, section-2, section-1, section-3, section-1, section-3,section-1, section-2, section-3, section-1, section-3, section-1.

4. Method of claim 1, said display panel or spatial light modulator comprising the capacity to allow data writing to any said section in random order.

5. Method of claim 4, said display panel or spatial light modulator further comprising the capacity to allow data writing to any row in each said section in random order.

6. Method of claim 5, said display panel or spatial light modulator further comprising the capacity to allow data writing to any word in each said row in random order.

7. Method of claim 1, said display plane comprising a screen, said screen displaying images from a spatial light modulator by a step of optical projection; said method further including a step of defining a number of color sub-panels on the display area of said spatial light modulator, each said color sub-panel being illuminated with a light of a different primary color.

8. Method of claim 7, each said section locating within the area of one of said color sub-panels.

9. Method of claim 8, said spatial light modulator comprising the capacity to allow data writing to any said section in random order.

10. Method of claim 8, said step of optical projection including the step of superimposing images from different said color sub-panels; said step of optical projection further including the steps of: optically splitting the projected image into a first image and a second image, both being identical;optically flipping said second image;optically stitching the flipped second image together with said first image to form a new image frame of a different aspect ratio.

11. System for displaying volumetric 3D images comprising: (1) an image projection unit;(2) a translucent screen rotating around a common axis;(3) an interfacing unit that relays the optical image projected from said image projection system onto the rotating screen while keeping the size, the orientation and the focus of the projected image invariant as the screen rotates;(4) a beam splitting reflector and a set of mirrors rotating about said common axis in unison with the rotating screen, said beam splitting reflector splitting the projected optical image from said interfacing unit into a transmitting part and a reflecting part, said set of mirrors guiding said transmitting part to project to the left half part of the screen with respect to said common axis and guiding said reflecting part to project to the right half part of said screen from the opposite side of the screen, said transmitting part and reflecting part stitching together as a fill image frame.

12. A frame distribution structure for a volumetric 3D display, said volumetric 3D display comprising a rotating display plane, said display plane rotating around an axis and sweeping a display volume, said frame distribution structure dividing the display volume of the volumetric 3D display into a number of zones according to distance to said axis, zones closer to said axis being inner zones, zones farther away from said axis being outer zones, said inner zones comprising less frame divisions, said outer zones comprising more frame divisions, said spacing between adjacent frame divisions in said inner zones and in said outer zones being roughly equal.