Model 6500/5 Spectrum Mode

This operating mode allows samples to be scanned between two given wavelengths at either 10nm, 5nm, 1nm or 0.2nm intervals. The scanned data is displayed in graphical form giving an ideal representation of the sample under test. A scan rate of 1200nm per minute can be achieved scanning at 5nm intervals, while even at 0.2nm intervals, an impressive 166nm per minute can be achieved. The y-axis limits of the spectrum can be manually set, or if required can be auto scaled after the scan has taken place to the highest and lowest points of the scan. If the optional printer is fitted to the instrument, a hard copy of a scan can be taken simply by pressing the print key. If the printer is not fitted, the scan data (as a series of data points) can still be taken by connecting the instrument to a personal computer via the RS232 port. By using a suitable terminal package on the personal computer, data can be sent to the PC when the print key is pressed on the instrument. Printed information includes the scan parameters and the following statistical information. A Centronics printer can also be fitted allowing spectrum scans to be printed on single sheet paper.

A peak and valley detection routine can be employed as part of the post scan analysis offered by the 6500 series. With this, any peak and valley that exceeds a selectable percentage of the difference between the maximum peak and minimum valley will be displayed. A noise filter value of 1%, 5%, 10% or OFF is selectable. Peaks and valleys can be viewed in tabular form, or can be labeled on the display, as the screenshot shows. If the optional internal printer, or a Centronics printer is fitted to the instrument, a hard copy of the statistics can be made simply by pressing the print key. If the printer is not fitted, the statistics can still be kept by downloading the data to the PC via the RS232 port by, again, simply pressing the print key.

Another post scan analysis feature of the 6500 series of instruments is calculating the area under a curve. This allows the user to select a peak from the performed scan, and the information box at the top of the display will show the calculated area along with the two user set wavelength points.

1Mb of internal memory can be used to store spectrum scans, or they can be stored on PCMCIA cards for later use. They can be recalled to the display with the normal statistical information and cursor measurement features available. The recalled scans can also be subsequently printed.

The instrument can be set to repeat a scan at a user set interval for a user set number of times. If required, the instrument can be set to automatically print the scan on completion of the auto-repeat scan.