PASCO CI-6630 User Manual
Instruction Sheet
for the PASCO
Model CI-6630
BROAD SPECTRUM LIGHT SENSOR
thumbscrew
with washer
GAIN
1
10
100
BROAD SPECTRUM
TARE
300nm -10,000nm
LIGHT SENSOR
CI-6630
cable with DIN
connectors
012-08541B
to computer
interface
shutter bracket
Introduction
The sensing element of the Broad Spectrum Light
Sensor (CI-6630) uses a thermopile as a detecting
element. Thermopile detectors are voltagegenerating devices that act like a miniature array of
thermocouples. The thermopile is a high output, thin
film, silicon-based device which has 48 thermopile
junctions. The active or “hot” junctions are
blackened to efficiently absorb radiation. The
reference or “cold” junctions are maintained at the
ambient temperature of the detector.
The blackening material used on the “hot” junctions
is capable of absorbing radiant energy from the ultra
violet to the far infrared range. To limit the spectral
sensitivity, optical filters and windows may be placed
in front of the detector. The window installed in the
Broad Spectrum Light Sensor’s detector is BaF
which has a spectral response from 300 to 10,000
CI-6630
Light Sensor
nanometers. The hermetically-sealed detector is heat
treated and filled with argon gas to improve long-term
stability.
The absorption of radiation by the blackened area
causes a temperature rise in the “hot” junctions, as
compared to the “cold” junctions of the thermopile.
This temperature difference across the thermocouple
junction causes the detector to generate a positive
voltage. If the active or “hot” junction cools to a
temperature less than the reference or “cold” junction,
the voltage output becomes negative.
The output of the thermopile detector is presented to a
gain selectable amplifier. The GAIN switch on the top
of the sensor is used to change the signal output (voltage)
of the sensor in experiments where the output signal is too
,
2
low, such as in dim light conditions, or when the signal
is too high, such as in bright light conditions.
Broad Spectrum Light Sensor 012-08541B
Equipment included:
• Broad Spectrum Light Sensor (CI-6630)
• 1/4-20 X .375” thumbscrew (617-008) with
0.250 I.D. washer (615-011)
• Shutter bracket (648-06954)
• 8-pin connector cable (514-06329)
Additional equipment required:
®
• ScienceWorkshop
• DataStudio
®
Using the Shutter Bracket with the Sensor
The spring-loaded shutter bracket keeps extraneous
radiated energy from heating the sensing element
either before or during measurements. The tab on the
front edge of the shutter bracket is for ensuring
constant spacing between the sensing element and a
hot object, such as when performing comparative
radiant energy measurements.
computer interface
software (version 1.8.5 or higher)
Mounting the Sensor to Experimental
Apparatus
Use the 1/4-20 threaded connector on the bottom of
the sensor box to secure the Broad Spectrum Light
Sensor to an experimental apparatus (Figure 2). The
alignment hole is for holding an alignment pin, which
is included on some PASCO products.
alignment hole
1/4-20
threaded
connector
Figure 2: Connector and alignment hole f or mounting
Attach the shutter bracket to the Infrared Sensor unit,
with the included thumbscrew and washer, as shown
in Figure 1. Do not over tighten the thumbscrew.
1/4-20 threaded
connector
shutter bracket
Figure 1: Attaching the shutter bra cket
Adjusting the Gain on the Sensor
The sensor has three gain settings: 1X, 10X and 100X.
The gain settings on the sensor, coupled with the userselectable gain on the
ScienceWorkshop interface,
allow for a very broad range of measurements with the
Broad Spectrum Light Sensor. (Note: Adjusting the
sensor’s gain only changes the signal voltage, not the
actual light intensity measurement. You can change the
gain to a maximum of +/- 10 volts.)
Adjust the gain for
the light conditions.
GAIN
1
10
100
BROAD SPECTRUM
LIGHT SENSOR
TARE
300nm -10,000nm
CI-6630
Tare
button
Figure 3: Setting the gain on the Infrared Sensor
2
®
Loading...