To obtain a good image in both cases of high magnification and low magnification by also altering the quantity of irradiation light corresponding to the alteration of photographing magnification.
The light passed through the aperture part of an aperture iris 28 is condensed by a condenser lens 40 to be allowed to irradiate the small region where a sample soln. flows of the flat passage of a flow cell 42. As the aperture iris 28 is stopped down the quantity of light is reduced and focus depth becomes large. The light passed through the flow cell 42 passes through a projection lens 94 or 96 through an object lens 90 and a mirror 92 to be photographed by a photographing means 114. The projection lenses 94, 96 are respectively set to one time and four times in magnification. When the sample soln. is photographed in low magnification, since a visual field is wide, light reaches the photographing means sufficiently and, even if the quantity of irradiation light is little, a bright image can be obtained. When the sample soln. is photographed in high magnification, since a visual field is narrow, the quantity of irradiation light is increased as compared with the case of low magnification.
NAKAGAWA MASAYUKI
MAEDA TADASHI
