Abstract: A reflector for improving the signal of spectrophotometer, the reflector comprising a truncated cone having a reflective inner surface and a conical axis, the truncated cone open at a larger axial end thereof, open at a smaller axial end thereof, and having an opening in the cone surface. The reflector returns specularly scattered light back to the surface of a sample, and therefore enhances the amount of collected light.

Abstract: A method to compensate for lamp spectrum shift, comprises exposing a first detector to a first light from a lamp, thereby generating a first signal indicative of intensity of said first light; exposing a second detector to a wavelength (.lambda.) of a second light from said lamp, thereby generating a second signal indicative of intensity of said wavelength of said second light, after said second light has interacted with a sample; determining a new color temperature (T.sub.1) of said first light using the following equationT.sub.1 =(F.sub.1 /A).sup.1/xwhere A=F.sub.i /(T.sub.i).sup.x,x=a color temperature exponent of said lamp, F.sub.1 =said first signal, F.sub.i =an initial reference signal, and T.sub.i =an initial color temperature corresponding to said initial reference signal; and determining a first compensated signal (I.sub.1) using the following equationI.sub.1 32 S.sub.1 /B.sub.1where ##EQU1## S1=said second signal, h=Planck's constant, c=speed of light in vacuum, and k=Boltzman constant.