LST400

LST400 Laser Shutter Specifications
Aperture Diameter	8.0 mm
Typical Beam Diameter used for Specs	6.0 mm
Maximum Shutter Repetition Rate	5 Hz
CW and Quasi-CW Optical Power Handling	50 W Max
Typical Damage Threshold, Aligned Polarization	300 mJ/cm2
Delay to Begin Opening after Command Open	10 ms
Opening Time Switching Speed	15 ms
Delay to Begin Closing after Command Close	5 ms
Closing Time Switching Speed	15 ms using CX4000B

LST400 Laser Shutter Specifications
Minimum FWHM Exposure Capability	30 ms using CX4000B
Thermal Power Dissipation Holding Open	4 W
Thermal Power Dissipation, Repetitive Cycling	8 W @ 3 Hz
Nominal Magnetic Winding Impedance	15 Ohms
Cable/Wire Type and Length	18 inches, 6 leads 22 g
Mounting Surface for Thermal Sinking	Base Plate
Position Sensors	Logic TTL, Require 5 VDC @ 20 mA
Weight	4 oz.
Size (see mechanical drawing)	3.80 x 2.06 x 0.64 Inches

Note: 3-D solid model available upon request (Solidworks or .stp file) Specifications updated on March 30, 2021

The LST400 laser shutter model is designed for use as a laser safety interlock and for some laser processing applications. The LST400 provides TTL output position sensors for the open and closed states as standard equipment. The thin body style and 8 mm aperture accommodate many popular laser sources. The –IR suffix replaces the over-coated aluminum mirror with gold, for use in the IR, including CO2. This option must be used for CO2 lasers.

Compatible system controllers are CX4000B or user-built circuits designed around 24 VDC.

Options are available using a suffix code system. Many options cannot be installed after manufacture, so choose carefully. Choose the –IR suffix for CO2 and IR use, starting at about 700 nm. The standard over-coated aluminum mirror is good from deep UV to about 4 microns. Special mirrors are not currently available, except for OEM applications. Cable options are available, call for details.

Special Considerations for this model include damage threshold assessment. The shutter is not designed for high energy, low repetition rate Q-switched lasers. See LSTXYW8 for these applications. Thermal mounting must be given strong attention if optical power dissipation is near the upper limit of the rating. For high activity processing, consider the LST200SLP.

Restricted use for this model is only limited to damage threshold and wavelength considerations. It can be used in any orientation with regards to gravity.

See the Mechanical Drawing tab for dimensions. Also see the Application Notes in the Technical Information menu for important operational issues including: thermal mounting, user-built circuits, polarization, lifetime, jitter, vacuum operation, and contamination. See the Product Matrix page to compare laser shutter models.

LST400 Laser Shutter Custom Options

Aperture Size Range	8mm to 12mm (round or obround)
Optics	Aluminum, Dielectric, Gold
Wire Length	Any length
Wire/Cable Type Wire Gauge	Teflon, Vinyl
Connector	Any 6 pin connector
Size	3.80 x 2.06 x .64 in., note: minimal size change can be designed
Identification	Engraving, Labels

LST400 Laser Shutter Mechanical Drawing
Note: 3-D solid model available upon request (Solidworks or .stp file)

LST400 Laser Shutter Electrical Drive

MODEL	LST400
Classification	Safety/Process
Number of Wire Leads, Std.	Six, 22 g
Cable or Wires – Length	18 inches
Cable/Wire Termination	MTA-100, AMP, P/N 643813-60
Recommended Controller and Voltage Present	Capacitor Discharge 24 V, 24 V PWM,- or our controllers
Shutter Winding Resistance	15 Ohms Nominal
Gravity Considerations	Symmetric Open/Close speed with base down More power needed for upside-down mounting
Typical Minimum Hold Open Voltage, Room Temperature	Room Temperature, 5 V
Typical Hold Open Power Dissipation as Heat	4 W
User Power Supply Notes	24 V, 1 A Rating, Surge Capacitor on output
User Drive Circuit/Cap Discharge	24 V, C=4 700 mmF, R=50 ohm, Use Flyback diode 1N4001
Nominal Winding Inductance	10 mH
User Drive Circuit/PWM Type	24 V for 50 ms, then drop to 7 V hold, Use 1N4001 Flyback
Color Codes and Function of Wires	PIN 1 Red, + to winding
	PIN 2 Black, – to winding
	PIN 3 Violet, Supply Regulated +5.0 VDC — 30 mA
	PIN 4 Yellow, NO Output from Sensor, TTL (reads high when shutter open)
	PIN 5 Orange, NC Output from Sensor, TTL (reads high when shutter closed)
	PIN 6 Blue, 5V Return and Sensor Ground