Method and system for calibrating an acoustic touchscreen

• US 9,046,966 B2
• Filed: 07/15/2013
• Issued: 06/02/2015
• Est. Priority Date: 06/21/2007
• Status: Active Grant

• Current Assignee: Elo Touch Solutions, Inc.
• Original Assignee: Elo Touch Solutions, Inc.
• Inventors: D'Souza, Henry M.
• Primary Examiner(s): Lee, Jr., Kenneth B
• Application Number:
  US13/942,545
• Publication Number:
  US 20140160083A1
• Time in Patent Office: 687 Days
• US Class Current: 1/1
• CPC Class Codes: G06F 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• CPC Class Codes: G06F 3/043 using propagating acoustic waves
• CPC Class Codes: G06F 3/0436 in which generating transducers and detecting transducers are attached to a single acoustic waves transmission substrate

Abstract

A method for calibrating an Acoustic Pulse Recognition (APR) touchscreen comprises touching an APR touchscreen at N comparison touch points. N audio profiles are acquired, and each of the N audio profiles are associated with one of the N comparison touch points. A predetermined calibration file is selected based on the N audio profiles. The predetermined calibration file comprises audio profiles associated with coordinate locations on the touchscreen.

Claims

1. A method for calibrating an Acoustic Pulse Recognition (APR) touch substrate having a plurality of microphones mounted thereon, comprising:

touching the APR touch substrate at N comparison touch points;

acquiring N audio profiles, each of the N audio profiles being associated with one of the N comparison touch points; and

selecting a predetermined calibration file from within a plurality of predetermined calibration files, said selecting being based on the N audio profiles, the predetermined calibration file comprising audio profiles associated with coordinate locations on the touch substrate, wherein each of said plurality of predetermined calibration files is acquired from APR touch substrates other than said APR touch substrate.

2. The method of claim 1, the selecting further comprising comparing the N audio profiles to at least first and second sets of audio profiles, the first and second sets being associated with first and second predetermined calibration files, respectively.

3. The method of claim 1, further comprising:

determining a difference between the N audio profiles and a first set of prerecorded audio profiles; and

comparing the difference to a difference threshold, the selecting being based on a relationship between the difference and the difference threshold.

4. The method of claim 1, further comprising:

comparing the N audio profiles to at least first and second sets of N pre-recorded audio profiles to determine at least first and second differences;

identifying a lowest difference from within the at least first and second differences; and

selecting the predetermined calibration file based on the lowest difference.

5. The method of claim 1, wherein N is less than a total number of audio profiles within the predetermined calibration file.

6. The method of claim 1, further comprising comparing the N audio profiles to a set of pre-recorded audio profiles, each of the pre-recorded audio profiles being based on at least one audio profile representative of at least one comparison touch point on the APR touch substrate.

7. A system for calibrating an Acoustic Pulse Recognition (APR) touch substrate, comprising:

the APR touch substrate;

a plurality of microphones mounted to the APR touch substrate; and

a processor configured to;

receive N audio profiles associated with N comparison touch points, the N audio profiles representative of signals detected by the plurality of microphones;

compare the N audio profiles to a plurality of sets of N pre-recorded audio profiles, each set of N pre-recorded audio profiles associated with a respective predetermined calibration file of a plurality of predetermined calibration files; and

select a predetermined calibration file from the plurality of predetermined calibration files based on the comparison of the N audio profiles to the plurality of sets of N pre-recorded audio profiles, the predetermined calibration file comprising audio profiles being representative of coordinates of touch points on the APR touch substrate, wherein each of said plurality of predetermined calibration files is acquired from APR touch substrates other than said APR touch substrate.

8. The system of claim 7, wherein N is less than a total number of the audio profiles within the predetermined calibration file.

9. The system of claim 7, the processor further configured to define N representative touch points having coordinates on the APR touch substrate, each of the N representative touch points corresponding to one of the N pre-recorded audio profiles within each of the sets.

10. The system of claim 7, wherein the N pre-recorded profiles are aggregate audio profiles representative of more than one touch point.

11. The system of claim 7, the processor further configured to compare the N audio profiles to at least first and second sets of pre-recorded audio profiles, the first and second sets being associated with first and second predetermined calibration files, respectively.

12. The system of claim 7, the processor further configured to:

determine a difference between the N audio profiles and a first set of pre-recorded audio profiles;

compare the difference to a difference threshold; and

select the predetermined calibration file based on a relationship between the difference and the difference threshold.

13. An Acoustic Pulse Recognition (APR) touch sensor, comprising:

an APR touch substrate; and

a memory configured to store a predetermined calibration file including a plurality of audio profiles acquired from APR touch substrates other than said APR touch substrate.