Optical Device for Blood Analysis, Analysis Apparatus Equipped With Such a Device

Abstract

Optical device ( 200 ) for blood analysis is in particular designed for the counting and differentiation of leucocytes in an automatic blood analysis apparatus and includes a light source ( 201 ) of the electroluminescent diode type in order to illuminate a blood sample ( 311 ) circulating in an optical tank.

1 . Optical device ( 200 ) for the counting and differentiation of leucocytes in an automatic blood analysis apparatus ( 20 ), characterized in that it comprises a light source ( 201 ) of the electroluminescent diode type in order to illuminate a blood sample circulating in an optical tank ( 300 ) along an injection axis (X 300 ). 
   
   
       2 . Device according to  claim 1 , characterized in that the diode ( 201 ) emits light the wave length of which is less than 600 nanometres. 
   
   
       3 . Device according to  claim 2 , characterized in that the diode emits light the wave length of which is less than 500 nanometres. 
   
   
       4 . Device according to  claim 1 , characterized in that it emits a source light beam ( 211 ) with a width comprised between 5 and 200 microns close to the injection axis. 
   
   
       5 . Device according to  claim 4 , characterized in that it emits a light beam with a width comprised between 90 and 120 microns. 
   
   
       6 . Device according to  claim 1 , characterized in that the light beam is emitted approximately in the direction of the tank, approximately transversely to the direction of flow of the sample. 
   
   
       7 . Device according to  claim 4 , characterized in that it comprises a rotatably-mounted transparent slide ( 220 ) arranged between the diode and the tank in order to be passed through by the source light beam ( 211 ) between two opposing surfaces. 
   
   
       8 . Device according to  claim 7 , characterized in that the transparent slide is rotatably mounted about an axis (X 220 ) approximately parallel to the movement of the blood sample in the tank. 
   
   
       9 . Device according to  claim 1 , characterized in that it comprises, beyond the optical tank, means for separation ( 205 ) by Fresnel losses for a resulting light beam ( 212 ) originating from the source light beam, separating said beam into an axially-resulting beam ( 213 ) and at least one beam resulting from Fresnel loss ( 214 ) constituted by Fresnel losses while passing the separation means ( 205 ). 
   
   
       10 . Device according to  claim 9 , characterized in that the separation means comprise at least one separation surface which is a surface of a transparent separation material, the axially-resulting beam having passed through the transparent material and the beam resulting from Fresnel loss having been reflected by the separation surface, said surface being slanted with respect to the resulting light beam, beyond the tank. 
   
   
       11 . Device according to  claim 9 , characterized in that it also comprises an apparatus ( 222 ) for measurement of the light of the axially-resulting beam and at least one other apparatus ( 223 ) for measurement of the light of the at least one beam resulting from loss. 
   
   
       12 . Device according to  claim 11 , characterized in that the measurement apparatuses ( 222 ,  223 ) comprise means for one measurement from a measurement of fluorescence. 
   
   
       13 . Device according to  claim 11 , characterized in that the measurement apparatuses ( 222 ,  223 ) comprise means for a measurement of the light losses in the axis. 
   
   
       14 . Device according to  claim 11 , characterized in that the measurement apparatuses ( 222 ,  223 ) comprise means for a measurement of the diffraction close to the axis. 
   
   
       15 . Device according to  claim 1 , characterized in that it also comprises means for measurement of the diffraction of the light beam at wide angles by the sample in the tank. 
   
   
       16 . Device according to  claim 1 , characterized in that it comprises, on the path of the beam before the tank, at least one diaphragm ( 202 ) to block spurious light. 
   
   
       17 . Haematology apparatus ( 20 ), in particular an automatic blood analysis apparatus, characterized in that it comprises a device ( 200 ) according to  claim 1 . 
   
   
       18 . Device according to  claim 10 , characterized in that it also comprises an apparatus ( 222 ) for measurement of the light of the axially-resulting beam and at least one other apparatus ( 223 ) for measurement of the light of the at least one beam resulting from loss. 
   
   
       19 . Device according to  claim 12 , characterized in that the measurement apparatuses ( 222 ,  223 ) comprise means for a measurement of the light losses in the axis. 
   
   
       20 . Device according to  claim 12 , characterized in that the measurement apparatuses ( 222 ,  223 ) comprise means for a measurement of the diffraction close to the axis.