Abstract
The light from a tungsten lamp was conveyed into a fresh heparinized non-hemolyzed bovine blood by one part of a bundle of fiber optics which contains 800 fiber optics (30 μ in diameter). The reflected light from the blood was guided by the other two parts, through which two electrical outputs (I610 and Ieoo) were obtained by means of photomultipliers with optical filters of maximum transmission at 610 mμ and 800 mμ, respectively. When the oxygen saturation of blood was changed, Iolo was changed, while Ieoo remained constant, and the logarithm of I610/I800 was linearly related to the oxygen saturation. Reflexi-bility (a) of red blood cell was calculated according to the equation derived from an ideal case. α at 610 mμ (aelo) and at 800 mμ (a800) with 100% oxygen satura-tion were 78.5 and 27.3%, when expressed as per cent of the reflexibility of mercury. aelo was 2.9 times as large α800. α800 did not change with the change of oxygen saturation, but aelo increased as oxygen saturation was increased. The relationship between I610 and oxygen saturation was comparable with that between I610/I800 and oxygen saturation. It is suggested that the change of reflected light dependent on oxygen saturation is due to the change in α610.
