Patent ID: 11928291
Assignee: nan
Field: Audio-visual technology (Electrical engineering)
Classification: CPC G  A  H | IPC G  H

Claim 11:
12. An image projection device having
a projection screen configured to display an image by projection light being irradiated from a surface side of the projection screen and a projector projection unit configured to project and display a predetermined image on the projection screen from the surface side of the projection screen,
the image projection device configured to recognize content of an input instruction corresponding to a touch operation when a user performs tap operation or double-tap operation as the touch operation on an image projected on the projection screen from the surface side of the projection screen using a finger of the user or a pointer and project an image in accordance with the recognized content of the input instruction on the projection screen, and

the image projection device comprising:
an imaging unit configured to:
image the image projected on the projection screen, and
acquire image data focused within a range of a predetermined distance from the projection screen to the surface side of the projection screen along a vertical direction of the projection screen, wherein
the predetermined distance is between 5 mm and 100 mm;

a reference data generating unit configured to generate reference data for specifying a position and a size of the image projected on the projection screen in an imaging range of the imaging unit based on the image data acquired by the imaging unit;
an image data extracting unit configured to:
extract image data in which a finger or a pointer with which a user performs operation on the image projected on the projection screen exists and in which the finger or the pointer is brought into focus in the image data obtained by the imaging unit, and
associate time data relating to time at which the image data is captured with the image data, wherein
the image data extracted by the image data extracting unit includes only image data in which the finger or the pointer exists within the predetermined distance from the projection screen along a vertical direction of the projection screen;

a position data generating unit configured to:
generate position data for specifying a position of the finger or the pointer in the imaging range of the imaging unit based on the image data extracted by the image data extracting unit, and
associate the generated position data with the image data;

an operation determining unit configured to determine content of operation performed with the finger or the pointer based on the position data and the time data associated with each piece of image data for a series of pieces of image data extracted in chronological order by the image data extracting unit; and
an input control unit configured to:
recognize content of an input instruction corresponding to the operation performed with the finger or the pointer based on:
the content of the operation determined by the operation determining unit,
the position data generated by the position data generating unit, and
the reference data generated by the reference data generating unit, and

control the projector to project an image in accordance with the recognized content of the input instruction on the projection screen, wherein
in a case where the operation determining unit recognizes, after image data in which the position of the finger or the pointer remains virtually unchanged is extracted for a predetermined period, image data in which the finger or the pointer exists at substantially the same position is extracted for the predetermined period again before a certain period of time has elapsed, the operation determining unit is configured to determine that the double-tap operation is performed with the finger or the pointer, and
in a case where the operation determining unit recognizes, after image data in which the position of the finger or the pointer remains virtually unchanged is extracted for the predetermined period, image data in which the finger or the pointer exists at substantially the same position is not extracted before the period of time has elapsed, the operation determining unit is configured to determine that the tap operation is performed with the finger or the pointer.