Opto-electrical ultrasound sensor and system
An opto-electrical ultrasound sensor, preferably for the use in medical diagnostics, comprising at least one light source ( 2 ), a photo detector ( 3 ) illuminated by the light source ( 2 ) and capable of producing an electrical signal indicative of the intensity of the light incident on the photo detector ( 3 ), and an optical ultrasound detector ( 4 ) located in the optical path between the light source ( 2 ) and the photo detector ( 3 ) and capable of modulating in response to an ultrasound signal the intensity of at least part of the light incident on photo detector ( 3 ) from the light source ( 2 ). The opto-electrical ultrasound sensor further comprises intensity adjustment means ( 5 ) for adjusting the intensity of the light incident on the photo detector ( 3 ) via the optical ultrasound detector ( 4 ).
1. An opto-electrical ultrasound sensor for use in medical diagnostics comprising:
at least one light source;
at least one photo detector illuminated by the light source and capable of producing an electrical signal indicative of intensity of light incident on the photo detector; and
at least one optical ultrasound detector located in an optical path between the light source and the photo detector and capable of modulating, in response to an ultrasound signal, the intensity of at least part of the light incident on the photo detector from the light source; and
an intensity adjustment for adjusting the intensity of the light signal incident on the photo detector via the optical ultrasound detector; wherein
the intensity adjustment is functionally connected to the photo detector and is adapted to adjust the intensity of the light as a predetermined function of time to perform a time gain control, thereby at least partially compensating for attenuation of the ultrasound signal as it emanates from increasingly greater depth in tissue being examined by said opto-electrical ultrasound sensor.
2. The opto-electrical ultrasound sensor according to claim 1 , wherein the intensity adjustment is adapted to control the light source to adjust the intensity of the light emitted by the light source.
3. The opto-electrical ultrasound sensor according to claim 1 , wherein the intensity adjustment comprises an attenuator located in the optical path from the light source to the photo detector via the optical ultrasound detector, said attenuator adapted to attenuate at least part of the light incident on the photo detector.
4. The opto-electrical ultrasound sensor according to claim 3 , wherein the attenuator comprises a Pockels cell.
5. The opto-electrical ultrasound sensor of claim 1 , wherein the intensity adjustment is adapted to reduce the intensity to prevent the electrical signal produced by the photo detector to exceed a pre-determined level.
6. The opto-electrical ultrasound sensor according to claim 1 , wherein the intensity adjustment is adapted to adjust the intensity in response to the electrical signal produced by the photo detector.
7. An ultrasound system comprising:
a transmission side having at least one transmission channel to generate an ultrasound signal; and
a reception side having at least one reception channel to detect and process the ultrasound signal; wherein:
the reception side comprises at least one opto-electrical ultrasound sensor according to claim 1 .
8. The ultrasound system according to claim 7 wherein the transmission side comprises at least one ultrasound transducer to generate the ultrasound signal, the at least one ultrasound transducer being different from the opto-electrical ultrasound sensor of the reception side.
9. The ultrasound system according to claim 8 , wherein the transducer comprises PVDF (Polyvinylidene Difluoride) as piezoelectric material.
10. The ultrasound system according to claim 7 , wherein the reception side comprises at least one low-voltage multiplexer.
11. The ultrasound system according to claim 10 , wherein the transmission side comprises at least one high-voltage multiplexer.
12. The ultrasound system according to claim 7 , wherein the reception side comprises at least one low-noise amplifier.
13. The ultrasound system of claim 12 , wherein an output of the photo detector is fed directly into an input of the low-noise amplifier.
14. The ultrasound system of claim 13 , wherein each low-noise amplifier is associated with one optical ultrasound detector.
15. The ultrasound system according to claim 12 , wherein an output of the low-noise amplifier is fed directly into a low-voltage multiplexer.
16. The ultrasound system according to claim 7 , further comprising an analog/digital converter.
17. The ultrasound system of claim 16 , wherein a signal emanating from a low-noise amplifier is fed directly into the analog/digital converter.
18. The ultrasound system according to claim 7 , further comprising a plurality of analog/digital converters, wherein each analog/digital converter is associated with one low-noise amplifier.
19. A method for detecting ultrasound for use in medical procedures which comprises:
illuminating a photo detector with a light source, the photo detector producing an electrical signal indicative of intensity of light incident on the photo detector;
modulating, in response to an ultrasound signal, the intensity of at least part of the light incident on the photo detector from the light source by means of an optical ultrasound detector located in an optical path between the light source and the photo detector; and
adjusting the intensity of the light signal incident on the photo detector via the optical ultrasound detector by an intensity adjustment; wherein
the intensity of the light signal is adjusted by the intensity adjustment as a predetermined function of time to perform a time gain control, thereby at least partially compensating for attenuation of the ultrasound signal as it emanates from increasingly greater depth in tissue being examined.