JPS6427532A - Acceleration pulse wave meter - Google Patents

Abstract

PURPOSE:To extend the life of a light emitting element and to prevent energy loss, by detecting the presence of a fingertip in a blood flow pickup on the basis of the output of the blood pickup and stopping the lighting of the light emitting element or limiting light emitting quantity when the absence of the fingertip is detected. CONSTITUTION:When a person to be measured inserts his fingertip 9 in a blood flow pickup, the light emitted from a light emitting element 2 transmits through the fingertip 9 of the person to be measured to be received by a photodetector 3. The variation in the quantity of the light received thereby is detected by a pulse wave detecting part 5 in an acceleration pulse wave converter 4. When the person to be measured pulls off his fingertip 9 from the blood flow pickup 1 after measurement, the quantity of the light received by the photodetector 3 increases suddenly. A light emitting quantity controller 8 detects that the fingertip 9 is pulled off from the blood flow pickup 1, on the basis of said change and immediately stops or limits the supply of a current to the light emitting element 2. At the time of reuse, the supply of a current to the light emitting element 2 is started by separate operation or it is detected that the quantity of the light received by the photodetector 3 is further reduced by inserting the fingertip 9 in the blood flow pickup 1 to automatically obtain a general use state.