How do I use the TrayCell in a double beam spectrophotometer?
It is not advisable to use a second TrayCell for reference measurements in a double beam spectrophotometer. This is because of the measurable differences between the optical characteristics from fibre to fibre. This property rules out a background correction using two optical matching TrayCells. But since a background correction is not necessarily required for standard measurements, a baseline correction is sufficient in most cases. If there is the need to improve the signal-to-noise ratio due to the discrepancy of light intensity from measurement to reference beam, it is recommended to weaken the reference beam at about 20% of its intensity. That can be done very easily with a simple pinhole, set in the reference beam. As a result, the area of the hole should be about 20% of the measuring beam area. Furthermore, an extension of the integration time may have a positive influence on the signal-to-noise ratio.
