Method and device for controlling projection of wearable apparatus, and wearable apparatus

Patent metadata

Field	Value
Publication number	US-9872002-B2
Application number	US-201414437112-A
Country	US
Kind code	B2
Filing date	Aug 26, 2014
Priority date	Apr 28, 2014
Publication date	Jan 16, 2018
Grant date	Jan 16, 2018

Abstract

A method and a device for controlling projection of a wearable apparatus, and a wearable apparatus are provided. With the projection method, a 3D profile of the object as projection screen is acquired by a 3D acquisition device disposed on the wearable apparatus; coordinates of vertices of the projection area on the object as projection screen are determined according to the acquired 3D profile of the object as projection screen; a projection plane is determined according to the determined coordinates of vertices; and the projection is controlled according to the angle between the projection plane and the center line of the projection view angle of the projection component, the distance between the geometrical center of the projection plane and the projection component and the 3D profile of the object as projection screen such that the projection picture projected by the projection component is clearly and steadily projection displayed in the projection area on the object as projection screen.

First claim

The invention claimed is:

1. A method for controlling projection of a wearable apparatus that is provided with a projection component, comprising:
acquiring a 3D profile of an object as a projection screen by a 3D acquisition device disposed on the wearable apparatus;
determining coordinates of vertices of a projection area on the object as the projection screen according to the acquired 3D profile of the object as the projection screen;
determining a projection plane according to the determined coordinates of the vertices; and
controlling the projection according to an angle between the projection plane and a center line of an projection view angle of the projection component, a distance between a geometrical center of the projection plane and the projection component, and the 3D profile of the object as the projection screen,
wherein a display luminance of a projection picture projected in the projection area on the object as the projection screen is corrected according to the 3D profile of the object as the projection screen at least by:
determining an extent of deformation of the projection screen through a calculation operation including an integral operation that is related to the 3D profile of the object as the projection screen; and
adjusting the display luminance of the projection picture according to the extent of deformation of the projection screen.

2. The method of claim 1 , wherein a plane with a minimum sum of variances of distances from the determined coordinates of the vertices is determined as the projection plane.

3. The method of claim 2 , wherein,
a shape of the projection picture projected by the projection component is adjusted according to the angle between the projection plane and the center line of the projection view angle of the projection component such that the projection picture projected onto the object as the projection screen adapts to a shape of the projection area on the object as the projection screen; and
a size of the projection picture projected by the projection component is adjusted according to the distance between the geometrical center of the projection plane and the projection component such that the projection picture projected onto the object as the projection screen adapts to a size of the projection area on the object as the projection screen.

4. The method of claim 3 , wherein,
a correction angle for keystone correction of the projection picture projected by the projection component is determined according to the angle between the projection plane and the center line of the projection view angle of the projection component; and
the projection picture projected by the projection component is keystone-corrected according to the correction angle.

5. The method of claim 3 , wherein,
a compression ratio for compressing the projection picture projected by the projection component is determined according to a formula

ϕ
=

L_
⁢
1

L_
⁢
0
*

(

d
1

/

d
0

)

;

a size of the projection picture projected by the projection component is adjusted to a size that is obtained after the projection picture projected by the projection component is compressed according to the compression ratio;
where φ is the compression ratio for compressing the projection picture projected by the projection component, L_1 is the size of the object as the projection screen, L_0 is a preset size of the projection screen, d 1 is a distance between the geometrical center of the projection plane and the projection component, and d 0 is a distance between the corresponding geometrical center of the projection plane and the projection component when the size of projection area equals the size of the projection screen.

6. The method of claim 3 , wherein,
the display luminance of the projection picture in the projection area on the object as the projection screen is determined according to a formula
L _out( x,y )= L _in( x,y )*∫( x,y,z );

the display luminance of the projection picture projected in the projection area on the object as the projection screen is corrected according to the determinate display luminance,
where L_out(x, y) is the display luminance of the projection picture at the location corresponding to a coordinate point (x, y) in the projection area on the object as the projection screen, L_in(x, y) is the display luminance of the display picture projected at the coordinate point (x, y), and ∫(x, y, z) denotes the integral operation and represents an integral of the three dimensional coordinate point in the 3D profile of the object as the projection screen that corresponds to the coordinate point (x, y) in the projection area on the object as the projection screen.

7. The method of claim 1 , wherein,
a shape of the projection picture projected by the projection component is adjusted according to the angle between the projection plane and the center line of the projection view angle of the projection component such that the projection picture projected onto the object as the projection screen adapts to a shape of the projection area on the object as the projection screen; and
a size of the projection picture projected by the projection component is adjusted according to the distance between the geometrical center of the projection plane and the projection component such that the projection picture projected onto the object as the projection screen adapts to a size of the projection area on the object as the projection screen.

8. The method of claim 7 , wherein,
a correction angle for keystone correction of the projection picture projected by the projection component is determined according to the angle between the projection plane and the center line of the projection view angle of the projection component; and
the projection picture projected by the projection component is keystone-corrected according to the correction angle.

9. The method of claim 7 , wherein,
a compression ratio for compressing the projection picture projected by the projection component is determined according to a formula

ϕ
=

L_
⁢
1

L_
⁢
0
*

(

d
1

/

d
0

)

;

a size of the projection picture

Assignees

• Boe Technology Group Co Ltd

Inventors

• Zhao Xingxing
• Chen Yanshun
• Xu Qiushi
• Li Yaohui

Classifications

• H04N9/3188

  Scale or resolution adjustment (scaling in general G06T3/40; resolution modifying circuits for displays in general G09G5/391) · CPC title

• H04N13/0275

  Electricity · mapped topic

• G01B11/00

  Measuring arrangements characterised by the use of optical techniques · CPC title

• H04N9/3194

  including sensor feedback · CPC title

• H04N9/3173

  wherein the projection device is specially adapted for enhanced portability · CPC title