THORLABS ELL14, Руководство по эксплуатации

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ELL14 Motorized SM1 Optic Rotator Chapter 4: Operation
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Chapter 4 Operation
Getting Started
Caution
Although the module can tolerate up to 8 kV of air discharge, it must be treated as an ESD sensitive device. When
handling the device, anti-static precautions must be taken and suitable anti-discharge appliances must be worn.
Do not expose the rotator to magnetic fields as this could affect the positioning and homing sensor operation.
When power is applied, do not connect or disconnect the ribbon cable connecting the USB/PSU adapter to the rotator
PCB. Always remove power before making connections.
Warning
If the device is operated over a prolonged time period, the motor housing may become hot. This does not affect motor
operation but may cause discomfort if contacted by exposed skin.
1. Perform the mechanical installation as detailed in Section 3.1
2. Turn on and boot up the host PC.
3. Connect the handset to the stage if required.
Caution
The unit is easily damaged by connections with incorrect polarity. Pin 1 of the connector on the PCB is marked with
an arrow (see Figure 5 and Figure 6) which should be adjacent to the red wire in the connecting cable.
1. Connect the stage to a 5V supply and switch ‘ON’. (A 5 V PSU is supplied with the ELL14K).
Caution
Boot up the PC BEFORE connecting the USB cable. DO NOT connect a powered ELL kit to a PC that is
not powered up and running.
2. Using the USB cable supplied, connect the handset to the PC.
3. If required, and wait for the drivers to be installed.
4. Home the stage. Homing is necessary to align the sensor and establish a datum from which all future moves
are measured.
4.1.1 Homing
Homing is achieved using a combination of a reflecting optical sensor (IR) for coarse (0.5 to 1.0 mm) positioning, then a magnetic
sensor for fine (1.0 µm resolution) positioning (the magnetic sensor is also used for positioning during subsequent moves). Using
the ELLO software, the user can modify the offset value to shift the homing position (up to a ¼ of turn). Furthermore, coarse
homing can be selected in a clockwise or counter clockwise direction (the switch between coarse to fine homing is always
performed in the same direction to guarantee repeatability).
4.1.2 Position Error Compensation
The rotator has a positioning error compensation algorithm. When moving from one position to another, the rotator detects the
error between the requested and actual positions and will calculate an error compensation value, which is then applied to the
next movement. The calculation is applied automatically and is continually updated, but generally the optimum value is calculated
within 2 to 6 motions.