Granted Patent B2

US 8,481,955 · App. 13/617,116 · Granted Jul 9, 2013

Abstract

Claims (37)

1. A method of signal processing in a dental radiology apparatus comprising an intraoral sensor that includes a detector having an active pixel array produced using biCMOS technology, the pixels being arranged in rows and columns, comprising:

selecting each row of the array;

for each row selected, sampling of the data values held by each pixel having been exposed to radiation;

generating a read signal from the sampled data values for the array's pixel;

applying, at the detector's input, an input reference signal (black-in); and

producing an output signal based on the array's read signal and an output reference signal (black-ref) representative of the detector's intrinsic electronic drifts and which is obtained at the detector output based on the input reference signal applied at the detector's input.

2. The method according to claim 1 , characterized in that the output signal is produced by forming a difference between the array's read signal and the output reference signal (black-ref).

3. The method according to claim 1 , characterized in that for each array row selected, after the first sampling step, the method includes a second sampling step of the data values obtained after resetting each pixel.

4. The method according to claim 3 , further including applying a resetting signal to each selected row between the two sampling steps.

5. The method according to claim 4 , characterized in that the array's read signal is generated by calculating the difference between the data values held by the array's pixels and obtained respectively after each sampling of the same pixel.

6. The method according to claim 1 , characterized in that the input reference signal is DC voltage.

7. The method according to claim 1 , characterized in that it includes a step of receiving the input reference signal that comes from an electronic module remote from the sensor.

8. The method according to claim 1 , characterized in that prior to the first sampling step, the pixel array is exposed to visible radiation coming from the conversion of an x-ray having passed through a tooth.

9. The method according to claim 1 , characterized in that the produced output signal is an analog output signal.

10. The method according to claim 9 , characterized in that the analog output signal is delivered by the sensor.

11. The method according to claim 9 , characterized in that it includes a step of converting the analog output signal into a digital output signal.

12. The method according to claim 1 , characterized in that it includes a step of transmitting the output signal to an electronic module remote from the sensor.

13. The method according to claim 12 , characterized in that a conversion step is performed in the electronic module.

14. A dental radiology apparatus comprising an intraoral sensor that includes a detector including an active pixel array produced using biCMOS technology, the pixels being arranged in rows and columns, comprising:

means for selecting each row of the array;

means for sampling the data values held by each pixel having been exposed to radiation, for each row selected;

means for generating a read signal from the sampled data values for the array's pixels;

means for applying, at the detector's input, an input reference signal; and

means for producing an output signal from the array's read signal and an output reference signal (black-ref) representative of the detector's intrinsic electronic drifts and which is obtained at the detector output based on the input reference signal applied at the detector's input.

15. The apparatus according to claim 14 , characterized in that the means for producing the output reference signal includes means for forming a difference between the array's read signal and the output reference signal (black-ref).

16. The apparatus according to claim 14 , further comprising means of applying a resetting signal to each selected row and whose pixel data values have been sampled a first time, the sampling means being adjusted to sample the data values held by each reset pixel.

17. The apparatus according to claim 16 , characterized in that the means for generating the read signal include means of forming the difference between the data values held by the array's pixels and obtained respectively after each sampling of the same pixel.

18. The apparatus according to claim 14 , wherein the input reference signal is a DC voltage.

19. The apparatus according to claim 14 , further including means of reception of the input reference signal that comes from an electronic module remote from the sensor.

20. The apparatus according to claim 14 , wherein the pixel array is exposed to visible radiation coming from the conversion of x-rays that have passed through a tooth.

21. The apparatus according to claim 14 , wherein the produced output signal is an analog output signal.

22. The apparatus according to claim 21 , wherein the sensor is capable of delivering the analog output signal.

23. The apparatus according to claim 21 , further including means of analog-digital conversion of the analog output signal into a digital output signal.

24. The apparatus according to claim 14 , further comprising an electronic module remote from the sensor and a link between the module and the sensor for transmitting the sensor's output signal to the module.

25. The apparatus according to claim 14 , wherein the electronic module comprises a means of analog-digital conversion.

26. The apparatus according to claim 14 , wherein the sensor has an x-ray converter that is capable of converting the x-rays that have passed through a tooth into visible radiation.

27. The apparatus according to claim 26 , wherein the biCMOS detector including the active pixel array is capable of converting at least one part of the visible radiation coming from the conversion of the x-rays into at least one analog electrical signal.

Assignments (9)