Table of Contents
Related Manuals for Cairn Dual OptoLED
Summary of Contents for Cairn Dual OptoLED
- Page 1 Specialists in Fluoresence Microscopy - DESIGN TO INTEGRATION roscopy - DESIGN TO INTEGRATION Dual OptoLED PRE1 PRE2 PRE3 Instruction Manual www.cairn-research.co.uk Free Phone: 08453301267 (UK only) Tel: +44 (0) 1795590140 Fax: +44 (0) 1795594510...
- Page 3 Our standard LED heads have built in protection to avoid damage, however if in any doubt then please check with Cairn as to the rated power of the supplied heads, and use accordingly. The OptoLED is typically supplied in conjunction with our modular microscope coupling system.
-
Page 5: Table Of Contents
Contents Introduction Installation Guide Front Panel Rear Panel Technical Summary General Operating Notes Specifications Technical support Appendix LED Head Connections Overload Protection... -
Page 7: Introduction
Introduction The Cairn OptoLED is capable of driving two LEDs independently, over a wide range of currents. For pulsed illumination, switching times of less than 100 nanoseconds are achievable, and digital control inputs to support this mode of operation are provided. The standard operating... -
Page 8: Installation Guide
CURRENT POWER POWER GATE GATE OVERLOAD OVERLOAD REMOTE REMOTE FRONT PANEL FRONT PANEL DUAL OPTOLED POWER SUPPLY LED ON CURRENT CURRENT POWER GATE OVERLOAD REMOTE FRONT PANEL DUAL OPTOLED POWER SUPPLY OFF/ GATE/ON' Switch This switch allows the digital control signals to be overridden. These signals are applied via the "GATE"... - Page 9 'REMOTE/FRONT PANEL' Switch This switch determines whether the unit is controlled by the optional remote slider or the front panel controls. The remote control slider plugs into the rear on the power supply, as described later. 'LED ON' Indicator This indicator is illuminated whenever the digital control signals (both from the “GATE”...
-
Page 10: Rear Panel
Rear Panel EXT LEVEL MONITOR EXT LEVEL MONITOR 5A FUSE REMOTE FEEDBACK FEEDBACK GATE 2 GATE 2 GATE 1 GATE 1 85 - 264 V AC 47 - 440Hz EXT LEVEL MONITOR FEEDBACK GATE 2 GATE 1 'EXT LEVEL' BNC and Switch This is an external analogue input for the LED drive level, active when the adjacent switch is in the “ON”... - Page 11 'ROTARY DIN' Socket This is an 8-pin locking DIN socket for connection to the LED head. In case you would like to make up your own custom LED heads, the connections are described in the Appendix. 'GATE 1' and 'GATE 2' BNC's The OptoLED has two "GATE"...
- Page 12 When looking at the front panel, the left hand preset controls the left hand bank. 'AUX' Connector This is not currently being used, but has been included to future-proof the controller for further development. 'REMOTE' Connector This connector is for the (optional) remote control slider. Please note, in order to control the unit using the remote control, the switch must be in the 'REMOTE' position on the front panel of the unit.
-
Page 13: Technical Summary
Technical summary Internal jumper links and Presets The controller contains two identical circuit boards, one for each LED. The circuit board nearer the front panel corresponds to the right-hand set of LED controls, and the function of each of the presets and jumper links is as follows. - Page 14 PRE1 This zeroes out any voltage offset in the optical feedback pathway within the controller. The procedure is to disconnect the LED head, and adjust for zero output on pin 7 (second pin from upper left) of IC2. This IC is the second one down from the top, near the left-hand edge of the board.
- Page 15 Page 9...
-
Page 16: General Operating Notes
General Operating Notes LED technology is continuing to develop rapidly. The first LEDs operated only in the red or infra-red, and were not particularly powerful. However, they are now available not only across the optical spectrum, but even extend into the near ultraviolet. Intensities have also increased by literally orders of magnitude, now rivalling incandescent lamps, and even beginning to compete with some arc lamps. - Page 17 feasible to do directly. Instead, a constant-current power supply with a variable current output is far more suitable, so this is what we are using here. However, just as a constant-voltage power supply has a maximum output current, so does a constant-current power supply have a maximum output voltage, and for general cost and efficiency reasons it is important to match the current or voltage limits to match what is reasonably to be expected.
- Page 18 increasing temperature, and with some types this effect can be quite significant, e.g. 10% or more. Unless the pulse duty cycle is quite short in comparison with the thermal time constant of the LED, the increase in temperature during the pulse can be enough to cause a noticeable droop in the light output.
- Page 19 To the extent that the spectral characteristics of an LED change just with the drive current (and not with temperature), then this effect can be avoided by using the variable pulsewidth facility. Here the instantaneous LED current is either a constant value (set by the current control as before) or zero, and one now varies the average LED intensity by varying the mark:space ratio of the pulse waveform.
-
Page 20: Specifications
Specifications Mains input voltage 85-260V, 50-60Hz, CE compliant Maximum output 20V Maximum output current 1A 2A or 5A, selectable by internal jumper links Optical switching times via "hold" inputs, on or off <100nsec Response time to change in external analogue input <10usec Response time of optical feedback circuit <10usec External analogue control voltage range 0 to+10V Digital inputs TTL level (0V or +5V nominal) -
Page 21: Technical Support
Technical Support E-mail: tech@cairn-research.co.uk Web: http://www.cairn-research.co.uk Address: Cairn Research Graveny Road Faversham Kent ME13 8UP Telephone: +44 (0) 1795590140 Fax: +44 (0) 1795594510 Page 15 Page 16... -
Page 22: Appendix
Appendix The information given here is provided to allow users to construct their own LED heads if they wish to do so. Alternatively - and perhaps more conveniently - it will allow heads supplied by us to be customised to use other LEDs if required. -
Page 23: Overload Protection
Overload Protection The overload protection is programmed by an RC network in the plug for the LED head. This network forms part of a voltage divider from the measured power signal. Normally the power signal is 100mV/W, except when an LED array is used (detected by another connection in the LED head plug), in which case the signal is 10mV/W to allow higher powers to be controlled. - Page 24 32.3K 27.6K 14.4K 12.3K 10.1K 7.7K 6.1K 4.3K 3.2K 100W 1.04K These resistor values correspond to tenfold higher power levels in array mode, which is signalled as described in the LED head connections section of this Appendix. Note that the highest power that can be metered is 20W (200W for an array, although that power can't be achieved in practice), but the overload circuitry can in theory measure power levels of up to 100W.
- Page 25 calculating C for a given time constant T is as follows. First calculate Re, which is given by R+1K in parallel with 100K, in series with Rp, i.e. Re = 1/{1/(R+1K) + 1/100K} + Rp. Then calculate the required value of C from C = T/Re.
Need help?
Do you have a question about the Dual OptoLED and is the answer not in the manual?
Questions and answers