Minolta reflectometer

Minolta reflectometer instructions for data downloading to a PC

Minolta CM-2002 spectrophotometer

Characteristics: solid angle of the measurement beam: 7.4deg ; incidence angle of measurement: 8deg ; measured area: diameter 8mm

In mode SCE (Specular Component Excluded), an internal light trap opens up and let the specular reflection of the source lamp onto the sample surface be captured and eliminated from the measurement. Only scattered light from the sample surface is measured. The Total Integrated Scatter (TIS) is measured and relates to the micro-roughness of the surface as: In mode SCI (Specular Component Included), the light trap is closed, therefore the source light bounces off it and gets to the sensor: the combination of reflected and scattered lights are measured. Specular reflected light will then come from the calculation of the difference SCI-SCE.

Procedure for internal memory data transfer to PC; 11/08/98 (M. Boccas)


1. PC and Spectr OFF: connect the RS232 cable to Spectr and COM port of PC

2. Turn ON PC and Spectr.

3. On Spectr:

- press DEL and MENU to go to menu

- press AVG to select DATA OUT

- press the DOWN KEY to enter data out menu

- press AVG to select SETUP and enter with DOWN KEY

- Select 9600 bauds, Even, 7 bits/char, 1 stop bit, Auto out Off, output to PC

- press MENU, press AVG to select REMOTE, enter with DOWN KEY

- the Spectr shows /REMOTE/ and is ready for data transfer

4. On PC (Windows):

-enter Start/Programs/ Accessories/Hyperterminal/Hyperterminal

- give name to your emulator/hyperterminal (for example "reflectometer")

- select the COM port used

- enter the same settings as in the Spectr (9600, even, 7, 1) and NONE for Flow control

- enter the FILE menu, choose Properties, then Settings, then Ascii setup, select "Append line" in the Ascii receiving section (so you can see all the commands and received data on different lines of your emulator)

- in the menu TRANSFER, start the Capture Text option

- Define a capture file (create a dummy one before) or use the default one proposed


- type DQR then Return to see the number of data sets in the Spectr memory card

- type SDR then Return

- type the number returned by DQR then Return
(see list of commands p86 Minolta manual)

- the Spectr display will show /OUTPUT/ during transfer
(Press DEL on Spectr anytime to interrupt transfer)

- the transfer ends with a E in the hyperterminal window

- stop the Capture in the TRANSFER menu

- put the data in Excell for plotting

Note: the SDR command downloads all the files in the memory card up to the number specified. If you haven't erased the memory card since last measurements, you will need to select only the wanted last files in Excell.


Total Integrated Scatter:

In theory, scattered light dependence on wavelength is given by:


where TIS is the total integrated scatter measured in 2pi str, d is the roughness height and l is the wavelength. Therefore, scattered light should be lower in the nearIR than in the blue. Particle size might modify that law if they are about the size of the wavelength.