Alternating light sources to reduce specular reflection

• US 8,212,857 B2
• Filed: 01/26/2007
• Issued: 07/03/2012
• Est. Priority Date: 01/26/2007
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Keam, Nigel
• Primary Examiner(s): Eng, David
• Application Number:
  US11/627,861
• Publication Number:
  US 20080180530A1
• Time in Patent Office: 1,985 Days
• Field of Search: 348/31
• US Class Current: 348/31
• CPC Class Codes: G02B 27/0018 with means for preventing ghost images anti-reflection coatings G02B1/11
• CPC Class Codes: G03B 15/02 Illuminating scene
• CPC Class Codes: G06F 3/0425 using a single imaging device like a video camera for tracking the absolute position of a single or a plurality of objects with respect to an imaged reference surface, e.g. video camera imaging a display or a projection screen, a table or a wall surface, on which a computer generated image is displayed or projected tracking a projected light spot to determine a position on a display surface G06F3/0386

Abstract

An interactive display in which alternating illuminators are used to reduce or cancel specular reflections. The interactive display includes multiple illuminators and at least one camera placed behind one or more display layers. The interactive display uses a phase management mechanism that controls alternation of phases of the interactive display. When in the first phase, the first illuminator is controlled to dominate over the second illuminator. When in the second phase, the second illuminator is controlled to dominate over the first illuminator. A consolidated image is then formulated using a combination of the first and second images. The consolidated image has reduced or eliminated specular reflections as compared to the first and second images alone.

Claims

1. An interactive display comprising:

one or more display layers that are at least partially transparent, the one or more display layers having a first side and a second opposing side;

a first illuminator positioned at a first location behind the one or more display layers, such that at least some light emitted from the first illuminator passes from the first illuminator through the first side and the one or more display layers towards an object positioned on the second opposing side of the one or more display layers during illumination of the first illuminator;

a second illuminator positioned at a second location behind the one or more display layers, such that at least some light emitted from the second illuminator passes from the first illuminator through the first side and the one or more display layers towards the object positioned on the second opposing side of the one or more display layers during illumination of the second illuminator;

a camera positioned behind the one or more display layers with the first and second illuminators, the camera being configured to take images of at least a portion of the first side of the one or more display layers;

a phase management mechanism configured to;

control alternation of phases of the interactive display, the interactive display having a plurality of phases including at least a first phase, a second phase, and a third phase;

when in the first phase, controlling the first illuminator to dominate over the second illuminator, and in the first phase causing the camera to take a first image;

when in the second phase, controlling the second illuminator to dominate over the first illuminator, and in the second phase causing the camera to take a second image; and

when in the third phase, controlling all illuminators, including the first illuminator and the second illuminator, to be turned off, and in the third phase causing the camera to take a third image;

an image construction mechanism configured to construct an input image using at least at least a portion of the first image, at least a portion of the second image, and at least a portion of the third image.

2. The interactive display in accordance with claim 1, wherein the image construction mechanism is configured to construct the input image using a consolidation of the first and second images and a subtraction of at least a portion of the third image.

3. The interactive display in accordance with claim 1, wherein:

the interactive display includes at least four phases including the first phase, the second phase, the third phase, and a fourth phase,

the phase management mechanism is further to turn both the first and second illuminators off when in the fourth phase, and in fourth phase causing the camera to take a fourth image, and

the image construction mechanism is further configured to construct the input image using at least a portion of the fourth image.

4. The interactive display in accordance with claim 3, wherein the image construction mechanism is configured to construct the input image using a consolidation of the first and second images and a subtraction of at least a portion of the third image and a subtraction of at least a portion of the fourth image.

5. The interactive display in accordance with claim 3, wherein the first and second phases are adjacent in time.

6. The interactive display in accordance with claim 5, wherein the third and fourth phases are adjacent in time.

7. The interactive display in accordance with claim 3, wherein the first and second phases interleave the third and fourth phases.

8. The interactive display in accordance with claim 1, wherein the camera is a first camera, the interactive display further comprising:

a third illuminator positioned at a third location behind the one or more display layers;

a fourth illuminator positioned at a fourth location behind the one or more display layers; and

a second camera positioned behind the one or more display layers,

wherein the phase management mechanism is further configured to;

when in the first phase, controlling the third illuminator to dominate over the fourth illuminator, and in the first phase causing the second camera to take a third image; and

when in the second phase, controlling the fourth illuminator to dominate over the third illuminator, and in the second phase causing the second camera to take a fourth image, and

wherein the image construction mechanism is configured to construct a second input image using at least at least a portion of the third image and at least a portion of the fourth image.

9. The interactive display in accordance with claim 1, wherein the phase management mechanism is configured to control the first illuminator to dominate over the second illuminator by turning the first illuminator on and turning the second illuminator off.

10. The interactive display in accordance with claim 9, wherein the phase management mechanism is configured to control the second illuminator to dominate over the first illuminator by turning the second illuminator on and turning the first illuminator off.

11. The interactive display in accordance with claim 1, wherein the first and second illuminators are infrared illuminators and the camera is an infrared camera.

12. The interactive display in accordance with claim 1, wherein:

the first illuminator constitutes an array of a first plurality of illuminators, wherein when the first illuminator is turned on, each of the first plurality of illuminators are turned on, wherein the second illuminator constitutes an array of a second plurality of illuminators, wherein when the second illuminator is turned on, each of the second plurality of illuminators are turned on, and

the camera constitutes an array of a plurality of cameras, wherein when the camera takes an image, each of the plurality of cameras takes a portion of the image.

13. The interactive display in accordance with claim 12, wherein each of the plurality of cameras corresponding to one of the first plurality of illuminators and one of the second plurality of illuminators, such that a majority of illuminated light received by the corresponding camera originates from either the corresponding one of the first plurality of cameras or the corresponding one of the second plurality of cameras.

14. An interactive display that utilizes a plurality of alternating phases, including:

one or more display layers that are at least partially transparent and that comprise a first side upon which an object is positioned and a second opposing side;

a first and second illuminator and a camera which are all positioned behind the one or more display layers on the second opposing side of the one or more display layers; and

a phase management mechanism, which comprises;

a phase detection mechanism configured to detect a current phase of the interactive display;

an illumination control mechanism configured to;

cause the first illuminator to generate more light than an amount of reduced light that is generated by the second illuminator when the phase detection mechanism detects the current phase should be a first phase, such that the first illuminator is caused to dominate over the second illuminator within the first phase, even though the second illuminator still emits the reduced light in the first phase;

cause the second illuminator to generate more light than an amount of reduced light that is generated by the first illuminator when the phase detection mechanism detects the current phase should be a second phase, such that the second illuminator is caused to dominate over the first illuminator within the second phase, even though the first illuminator still emits the reduced light in the second phase; and

cause all illuminators, including the first illuminator and the second illuminator, to generate no light when the phase detection mechanism detects the current phase should be a third phase; and

a camera control mechanism configured to take a first picture of at least a portion of the one or more display layers when the phase detection mechanism detects the current phase should be the first phase, to take a second picture of the portion of the one or more display layers when the phase detection mechanism detects the current phase should be the second phase, and to take a third picture of the portion of the one or more display layers when the phase detection mechanism detects the current phase should be the third phase,

wherein an image is constructed using at least a portion of the first picture, at least a portion of the second picture, and at least a portion of the third picture.

15. In an image construction mechanism for use in an interactive display that includes a plurality of alternating phases, one or more display layers that are at least partially transparent, a first and second illuminator and a camera positioned at different locations behind the one or more display layers, a method for constructing an image comprising:

during a first phase, turning on a first illuminator which is positioned to illuminate a first side of one or more display layers of the interactive display so as to emit light from the first illuminator through the first side and the one or more display layers towards an object on a second and opposing side of the one or display layers during the first phase, and while refraining from turning on a second illuminator during the first phase, the second illuminator also being positioned to illuminate the first side of the one or more display layers;

taking a first image by a camera of at least a portion of the first side of the one or more display layers during the first phase;

during a second phase, turning on a second illuminator which is positioned to illuminate the first side of the one or more display layers of the interactive display so as to emit light from the second illuminator through the first side and the one or more display layers towards the object on the second and opposing side of the one or display layers during the second phase, and while refraining from turning on the first illuminator during the second phase;

taking a second image by the camera of the portion of the first side of the one or more display layers during the second phase;

during a third phase, turning off all illuminators, including the first illuminator and the second illuminator;

taking a third image by the camera of the portion of the first side of the one or more display layers during the third phase; and

an act of constructing an input image using a portion of the first image, a portion of the second image, and a portion of the third image.

16. The method in accordance with claim 15, wherein a portion of the first image that is not used in the constructed input image includes a specular reflection of the first image.

17. The method in accordance with claim 16, wherein a portion of the second image that is not used in the constructed input image includes a specular reflection of the second image.

18. The method in accordance with claim 15, wherein the third image includes the portion of the first side of the one or more display layers as illuminated by ambient lighting.