Sutter Instrument Lambda 421, Руководство по эксплуатации

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LAMBDA 421 OPERATION MANUAL – REV. 1.00N (20170623)
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supported by imaging software. The DG-4 circuit board was adapted to control the selection
of the active LED and the operating current for that LED.
The new Lambda 421 system combines four of our high power LEDs and their drivers, a
control circuit board from the new USB version of the DG-4 and the OBC to form a compact,
complete light source that functions like a DG-4 without any moving parts.
3.5 Understanding the Basic Operation of the Lambda 421
3.6 Manual control
The 421 has four LED controllers based on the Sutter Instrument Lambda TLED+
controllers. All of the basic controls of the TLED+ are maintained in the 421. First, there is a
system power switch located on the right of the cabinet face. Next to the switch is an
indicator lamp that shows red when the power supply is in operation. The controls for the
four LED drivers are arranged in four groups, each labeled CHANNEL 0 through CHANNEL
3. The channel number ties into the optical configuration in that it represents: The number
of reflects required to reach the common output port. The apparent incongruity of the 421’s
scheme vs. the DG-4’s Filter 0 is considered a shutter function and the 4 selectable optical
paths are numbered 1-4, is resolved by the arrangement of the 421’s front panel’s controls
and a somewhat altered set of external control commands.
Each channel has a two selector switches and a knob on the front panel. The right-most
switch in each group is labeled ON/OFF/TTL from top to bottom. Selecting the middle
position (OFF) turns the LED off. Setting the switch to the top position (ON), turns the on.
When selecting the lowest position (TTL), the channel is controlled by the DG-4 interface
circuit board. The switch to the left is labeled INT./EXT. In the upper position (INT.), the
internal current reference is selected. In the lower position (EXT.), the current level is under
the control of the DAC setting for whatever filter value is currently selected.
Selecting ON or OFF, and INT., the output is completely under manual control. Select TTL
and EXT., the unit is under control of the DG-4 interface. One can also use a combination of
manual and automatic switch setting if desired. For instance:
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If selecting TTL and INT. for a particular channel, the LED turns on and off under
control of the DG-4 interface, but the DAC output setting for selected filters has no effect
on this channel.
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If selecting EXT and either ON or OFF for a particular channel, the DG-4 interface will
not control the channel if the channel is gated on or off, but the current for the channel
will be controlled by the DAC setting for the currently selected filter.
The knob for each channel offers the ability to manually attenuate the current. The
attenuation is active no matter what mode or combination of modes is used so long as the
channel is turned on by the logic or the manual switch. If the EXT. mode is used and the DAC
values have reduced the current, the knob will further reduce the current proportionally, as
it would in any other mode.
The 421 was designed for LEDs that required 5 amps for maximum output. In some cases it
is desirable to use LEDs with a lower maximum current. Often certain desirable wavelengths
are not available in the more potent packages. The driver circuits can be turned down to
whatever reduced value of maximum current is required. The DAC input and the knob will