Biological information imaging apparatus and biological information imaging method

Abstract

A biological information imaging method includes a first measurement step to measure an acoustic wave ( 54 ) generated by light ( 53 ) with which a living body ( 51 ) is irradiated from a light source ( 50 ) and which is absorbed by tissue ( 52 ) in the living body, a storage step to store first information obtained in the first measurement step, a second measurement step to measure an acoustic wave ( 54 ) generated by light ( 53 ) with which the living body ( 51 ) is irradiated from the light source ( 50 ) and which is absorbed by the tissue ( 52 ) in the living body, and a processing step to generate an image of information of the tissue in the living body by using second information obtained in the second measurement step, and the first information stored in the storage step.

1 . A biological information imaging apparatus comprising:
 a light source, said light source being arranged to irradiate a sample with light at a first timing and to irradiate the sample with the light at a second timing which is different from the first timing;   an acoustic wave detector unit configured to detect a first acoustic wave generated by irradiating the sample with the light at the first timing and convert the first acoustic wave into a first electric signal and to detect a second acoustic wave generated by irradiating the sample with the light at the second timing and convert the second acoustic wave into a second electric signal;   an information processing unit configured to obtain first information based on the first electric signal, obtain second information based on the second electrical signal, and obtain difference information representing a difference between the first information and the second information; and   a heart rate measurement unit configured to measure a heart rate of the sample,   wherein said light source is arranged to irradiate the sample with the light at the second timing when the heart rate measured by said heart rate measurement unit is different from that at the first timing.   
     
     
         2 . The biological information imaging apparatus according to  claim 1 , wherein said light source is arranged to irradiate the sample with the light at the second timing when a shape of the sample is different from that at the first timing. 
     
     
         3 . The biological information imaging apparatus according to  claim 1 , wherein said information processing unit is configured to obtain a first signal in frequency domain by transforming the first electric signal, obtain a second signal in frequency domain by transforming the second electric signal, a difference signal in frequency domain representing a difference between the first signal and the second signal in frequency domain, and obtain an image based on the difference signal in frequency domain. 
     
     
         4 . The biological information imaging apparatus according to  claim 3 , wherein said information processing unit is configured to obtain a signal in space domain by transforming the difference signal in frequency domain and obtain the image based on the signal in space domain. 
     
     
         5 . A biological information imaging apparatus comprising:
 a light source, said light source being arranged to irradiate a sample with light at a first timing and irradiate the sample with the light at a second timing which is different from the first timing;   an acoustic wave detector unit configured to detect a first acoustic wave generated by irradiating the sample with the light at the first timing and convert the first acoustic wave into a first electric signal and to detect a second acoustic wave generated by irradiating the sample with the light at the second timing and convert the second acoustic wave into a second electric signal;   an information processing unit configured to obtain first information based on the first electric signal, obtain second information based on the second electrical signal, and obtain difference information representing a difference between the first information and the second information; and   a blood pressure measurement unit configured to measure a blood pressure of the sample, wherein said light source is arranged to irradiate the sample with the light at the second timing when the blood pressure measured by said blood pressure measurement unit is different from that at the first timing.   
     
     
         6 . The biological information imaging apparatus according to  claim 5 , wherein said light source is arranged to irradiate the sample with the light at the first timing when the heart rate by the heart rate measurement unit is high and irradiate with the light at the second timing when the blood pressure measured by said blood pressure measurement unit is diastolic blood pressure. 
     
     
         7 . The biological information imaging apparatus according to  claim 5 , wherein said light source is arranged to irradiate the sample with the light at the second timing when a shape of the sample is different from that at the first timing. 
     
     
         8 . The biological information imaging apparatus according to  claim 5 , wherein said information processing unit is configured to obtain a first signal in a frequency domain by transforming the first electric signal, obtain a second signal in the frequency domain by transforming the second electric signal, a difference signal representing a difference between the first signal and the second signal in the frequency domain, and obtain an image based on the difference signal. 
     
     
         9 . The biological information imaging apparatus according to  claim 8 , wherein said information processing unit is configured to obtain a signal in a space domain by transforming the difference signal in the frequency domain and obtain the image based on the signal in the space domain. 
     
     
         10 . A biological information imaging apparatus comprising:
 a light source, said light source being arranged to irradiate a sample with light at different timings;   an acoustic wave detector unit configured to detect acoustic waves generated by irradiating the sample with the light at the different timings and convert the acoustic waves into electric signals; and   an information processing unit configured to obtain signals in a frequency domain by transforming the electric signals, obtain a difference signal in the frequency domain representing a difference between the signals in the frequency domain, and obtain an image based on the difference signal in the frequency domain.   
     
     
         11 . The biological information imaging apparatus according to  claim 10 , wherein said information processing unit is configured to obtain a signal in a space domain by transforming the difference signal in the frequency domain and obtain the image based on the signal in the space domain.