Ocean Optics S2000 - Manual (Page 45)

LS-450 Blue LED Pulsed Light Source
The LS-450 B LUE LED P ULSED L IGHT S OURCE is a compact, low-cost light-emitting diode that produces pulsed or
continuous spectral output at 470 nm -- the blue region -- for high-sensitivity emission fluorescence measurements.
The LS-450 excitation source can be combined with other sampling optics for fluorescence applications.
Operation
1. Plug the wall transformer into a standard 110V outlet and into the back of the LS-450.
2. Screw an optical fiber onto the SMA connector on the front of the light source.
Using the Continuous Mode
1. Turn the switch on the back of the LS-450 to “contin.” The continuous mode simply means that the light
coming from the LS-450 is continuous.
2. To turn the lamp off, simply change the position of the switch to "off."
Using the Pulsed Mode
1. Plug one end of the DB-15 accessory connector into the back of the LS-450 and the other end into the back of
the S2000.
2. Turn the switch on the back of the LS-450 to “pulsed.” for pulsed mode of operation.
3. The pulsing of the LS-450 is controlled through the spectrometer. Remove your spectrometer from its housing.
Do not tamper with the optical bench. (If you have more than one channel in your system, you may have to
disconnect the channels from one another. The master spectrometer is always on the bottom of a multiple
channel system.)
4. In the center of the green circuit board, near the optical bench, find Jumper Block 3, labeled JP3. Jumper
Block 3 consists of 10 pins. The pins are labeled by rows: /16, /14, /12, /10 and 2. See the following chart for
which pins must be jumpered according to how many pulses per second you need for the A/D converter you
have interfaced to your S2000. (The default setting from the factory is /16)
For example, if you have an ADC1000 A/D converter, you have four choices for how many pulses per second
can come out of your LS-450: 976, 244, 60 and 15. If you select 244 pulses per second, place a jumper over
the pins next to the /14 label.
5. When using the pulsed flash mode, the user needs to ensure that a constant number of flashes occurs for every
integration cycle. To achieve a constant number of flashes per integration cycle, the integration time must be a
multiple of that shown in the table below. Integration times are set in the software. In OOIBase32, set the
integration time in the acquisition dialog bar above the graph area (See the
OOIBase32 Operating Software
Manual for more information about the integration time.)
Light Sources: LS-450
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S2000 JP3 Post #
DAQ700
Frequency (Hz)
ADC500 / SAD500
Frequency (Hz)
ADC1000
Frequency (Hz)
/16 98.0 488.0 976.0
/14 24.0 122.0 244.0
/12 6.1 30.0 60.0
/10 1.5 7.6 15.2
S2000 JP3 setting
Integration time for
DAQ700 must be a
multiple of
Integration time for
ADC500 / SAD500 must
be a multiple of
Integration time for
ADC1000 must be a
multiple of
/16 512 128 64
/14 128 32 16
/12 32 8 4
/10 8 (with a min. value of 24 ms) 4 4