Blood coagulation detection device and method
A blood coagulation detection device includes a micro channel unit, an optical signal unit, an opto-electronic conversion circuit, an amplifier circuit, and a filter circuit. The micro channel unit has a sample detection area. The optical signal unit transmits a reference light to the micro channel unit so as to form a message light. The opto-electronic conversion circuit receives the message light and converts the message light into an electrical signal. The amplifier circuit is electrically connected to the opto-electronic conversion circuit for amplifying the electrical signal. The filter circuit is electrically connected to the amplifier circuit for filtering the amplified electrical signal.
1. A blood coagulation detection device, comprising:
a micro channel unit having a sample detection area;
an optical signal unit for transmitting a reference light to the micro channel unit so as to form a message light;
an opto-electronic conversion circuit for receiving the message light and converting the message light into an electrical signal;
an amplifier circuit electrically connected to the opto-electronic conversion circuit for amplifying the electrical signal; and
a filter circuit electrically connected to the amplifier circuit for filtering the amplified electrical signal;
wherein the optical signal unit measures the blood coagulation by transmitting the reference light to the micro channel unit;
the filter circuit comprises a first filter circuit electrically connected to the amplifier circuit, and a second filter circuit electrically connected to the first filter circuit;
the first filter circuit is a notch filter; and
the central frequency of the notch filter is set to be 60 Hz.
2. The blood coagulation detection device as claimed in claim 1 , wherein the optical signal unit includes a light emitting element and a light detecting element.
3. The blood coagulation detection device as claimed in claim 2 , wherein the light emitting element is a light emitting diode and the light detecting element is a photoresistor.
4. The blood coagulation detection device as claimed in claim 3 , wherein the light emitting diode is a green light emitting diode.
5. The blood coagulation detection device as claimed in claim 1 , wherein the opto-electronic conversion circuit is a bridge circuit.
6. The blood coagulation detection device as claimed in claim 5 , wherein the bridge circuit is a Wheatstone bridge or a Kelvin bridge.
7. The blood coagulation detection device as claimed in claim 1 , wherein the second filter circuit is a fourth-order low pass filter.
8. The blood coagulation detection device as claimed in claim 7 , wherein the fourth-order low pass filter has a cut-off frequency in the range of 20 Hz to 30 Hz.
9. The blood coagulation detection device as claimed in claim 7 , wherein the fourth-order low pass filter is a Butterworth filter.
10. The blood coagulation detection device as claimed in claim 1 , wherein the micro channel unit further includes a micro channel which is connected to the sample detection area.
11. The blood coagulation detection device as claimed in claim 1 , wherein the sample detection area receives a blood sample.
12. The blood coagulation detection device as claimed in claim 11 , wherein the blood sample is a whole blood sample.
13. The blood coagulation detection device as claimed in claim 1 , wherein the amplifier circuit is an instrumentation amplifier.
14. The blood coagulation detection device as claimed in claim 1 , wherein the second filter circuit has four first resistors and four second resistors, each of the first resistors is selected to have a same resistance value.
15. The blood coagulation detection device as claimed in claim 14 , wherein the second filter circuit has four capacitors, each of the capacitors is selected to have a same capacitance value.
16. A blood coagulation detection method, comprising:
providing a micro channel unit, which has a sample detection area in which a blood sample is placed;
providing an optical signal unit, which emits a reference light to the blood sample for forming a message light;
providing an opto-electronic conversion circuit, which receives the message light and converts the message light into an electrical signal;
providing an amplifier circuit, which amplifies the electrical signal; and
providing a filter circuit, which performs a filtering to the electrical signal that has been amplified by the amplifier circuit;
wherein the optical signal unit measures the blood coagulation by transmitting the reference light to the micro channel unit;
the filter circuit includes a first filter circuit electrically connected to the amplifier circuit, and a second filter circuit electrically connected to the first filter circuit;
the first filter circuit is a notch filter; and
the central frequency of the notch filter is set to be 60 Hz.
17. The blood coagulation detection method as claimed in claim 16 , wherein the optical signal unit includes a light emitting element and a light detecting element.
18. The blood coagulation detection method as claimed in claim 17 , wherein the light emitting element is a light emitting diode and the light detecting element is a photoresistor.
19. The blood coagulation detection method as claimed in claim 16 , wherein the opto-electronic conversion circuit is a bridge circuit.
20. The blood coagulation detection method as claimed in claim 16 , wherein the second filter circuit has four first resistors and four second resistors, each of the first resistors is selected to have a same resistance value.