Shutter head unit
Shutter Head Unit
Purpose and Functionality
The Shutter Head Unit is a critical component in laser systems, designed to control the path of the laser beam. It employs a rotary solenoid to flip a Supermax coated Silicon mirror in and out of the beam’s path.
When the shutter is closed, the beam is deflected onto a water-cooled beam dump, effectively stopping the beam from continuing along its original path. When the shutter is open, the beam passes straight through the unit, allowing it to proceed unimpeded.
The open position corresponds to the electrically activated state of the solenoid. This means that in the event of a power failure, the shutter will automatically close due to the force provided by a spring. This feature enhances the safety of the system by ensuring that the beam is blocked when there is no power.
The status of the shutter is indicated by LEDs on the shutter head: red for open and green for closed. The open and close positions are detected by opto-reflective switches, providing a reliable method of status detection.
Technical Specifications
Power is supplied to the Shutter Head Unit via a 9-pin D plug connector. The open/close status of the shutter can also be monitored through this connector. An optional Laser Shutter Controller, LSC01, can be used to supply power and monitor the status of the shutter.
The shutter is designed as a safety shutter, not intended for brief timing exposures. Using the LSC01, typical opening and closing times have been measured at 30 and 60 msec respectively. These times cannot be equalised due to the limitations of the solenoid. The clear aperture of the shutter is 19mm.
The beam dump is water-cooled via connectors (6/4 M6). The required water flow rate depends on the temperature rise (ΔT) and the laser power (P). For example, for a 10° rise in water temperature and a laser power of 500W, the flow rate should be 0.7 litres/min.
The shutter heads are equipped with retractable screw rings for mounting to a beam pipe. Before installing the shutter, it is important to ensure that the beam is centred to the beam pipe. Also, note that there is an input and output side to the shutter. Sending the beam in from the wrong side will cause it to hit the rear of the mirror mount.
The shutter is designed to operate in any orientation, providing flexibility in system design and setup.