377_gvsgalvoscanners_10
3770_gvsgalvoscanners_10
4419_gvs001_sgl

Galvo Mirror Systems: Beam Diameter

PrintEmail

Small Beam Diameter Scanning Galvo Mirror Systems




  • For Small(<5mm) Beam Diameters
  • Choice of Mirror Coatings
  • 1D and 2D Kits Available
  • Easy Integration into OEM Systems
  • Analog Control Electronics

Features

  • Single- and Dual-Axis Systems
  • Moving Magnet Motor Design for Faster Response
  • High-Precision Optical Mirror Position Detection
  • Analog PD Control Electronics with Current Damping
    and Error Limiter
  • Choice of Mirror Coatings:
    • Protected Silver (GVS001 and GVS002)
      500 nm to 2.0 µm
    • Protected Gold (GVS101 and GVS102)
      800 nm to 20.0 µm
    • Broadband Dielectric E02 (GVS201 and GVS202)
      400 nm to 750 nm
    • High-Power Dual-Band K13 (GVS301 and GVS302)
      532 and 1064 nm
  • Custom Coatings (e.g., Aluminum) Available upon Request

These high-speed Scanning Galvanometer Mirror Positioning Systems are designed for integration into OEM or custom laser beam steering applications that utilize laser beams smaller than 5 mm in diameter. Each system includes a single- or dual-axis galvo motor and mirror assembly, associated driver card(s), and driver card heatsink(s). A low noise, linear PSU (GPS011) and motor/mirror assembly heatsink (GHS003) are available separately.

 

Key Specifications
Max Beam Diameter 5 mm
2-Axis System Beam Offset 10 mm
Wavelength Range
(Ravg > 95%)
GVS00x: 500 nm - 2.0 µm
GVS10x: 800 nm - 20.0 µm
GVS20x: 400 nm - 750 nm
GVS30x: 532 nm and 1064 nm
Repeatability 15 μrad
Damage Threshold
GVS00x (Silver)
GVS10x (Gold)
GVS20x (E02)
GVS30x (K13)

3 J/cm2 at 1064 nm, 10 ns pulse
2 J/cm2 at 1064 nm, 10 ns pulse
0.25 J/cm2 at 532 nm, 10 ns pulse
5 J/cm2 at 1064 nm, 10 ns pulse
Linearity 99.9%
Max Scan Angle
(Mechanical Angle)
±12.5°
(w/ 0.8 V/deg scaling)
Full Scale Bandwidth DC to 100 Hz Sq wave,
DC to 250 Hz Sine wave
Small Angle (±0.2°) Bandwidth DC to 1 kHz
Small Angle Step Response 300 µs
Optical Position Sensor Output 40 to 80 µA
Power Supply Requirements ±15 to ±18 VDC

 

Galvo Motor/Mirror Assembly
The galvo consists of a galvanometer-based scanning motor with an optical mirror mounted on the shaft and a detector that provides positional feedback to the control board. The moving magnet design for the GVS series of galvanometer motors was chosen over a stationary magnet and rotating coil design in order to provide the fastest response times and the highest system resonant frequency. The position of the mirror is encoded using an optical sensing system located inside of the motor housing.

Due to the large angular acceleration of the rotation shaft, the size, shape and inertia of the mirrors become significant factors in the design of high performance galvo systems. Furthermore, the mirror must remain rigid (flat) even when subjected to large accelerations. All these factors have been precisely balanced in our galvo systems in order to match the characteristics of the galvo motor and maximize performance of the system.

The mirrors are available from stock with silver, gold, broadband or high power dual band coatings. Custom coatings (e.g., aluminum) are available on request.

 

Scanning Galvo Mirror Assembly and Driver Board
All Thorlabs scanning galvo mirror systems feature a mounted single or dual axis mirror/motor assembly and driver card(s). Shown to the left is the GVS301 1D galvo mirror and driver card with heatsink. The mirror assembly feature multiple mounting holes and a rotatable collar mount for the mirror/motor. These small 5 mm galvo mirrors feature a plug style connector to the mirror assembly. Please see below for additional mounting options and accessories.

Servo Driver Board (All Systems)
The Proportional Derivative (PD) servo driver circuit interprets the signals from the optical position detecting system inside the motor and then produces the drive voltage required to rotate the mirror to the desired position. The scanner uses a non-integrating, Class 0 servo that is ideal for use in applications that require vector positioning (e.g., laser marking), raster positioning (printing or scanning laser microscopy), and some step-and-hold applications. Furthermore, the proportional derivative controller gives excellent dynamic performance. The circuit includes an additional current term to ensure stability at high accelerations. The same driver board is used in all our galvo systems.

 

System Operation
The servo driver must be connected to a DC power supply, the galvo motor, and an input voltage source (the monitoring connection is optional). For continuous scanning applications, a function generator with a square or sine wave output is sufficient for scanning the galvo mirror over its entire range. For more complex scanning patterns, a programmable voltage source should be used. The ratio between the input voltage and mirror position is switchable, either 0.5, 0.8 or 1. When set to 0.8, the ±10 V input will rotate the mirror over its full range of ±12.5°. The control circuit also provides monitoring outputs that allow the user to track the position of the mirror. In addition, voltages proportional to the drive current being supplied to the motor and the difference between the command position and the actual position of the mirror are supplied by the control circuit.

Closed-Loop Mirror Positioning
The angular orientation (position) of the mirror is optically encoded using an array of photocells and a light source, both of which are integrated into the interior of the galvanometer housing. Each mirror orientation corresponds to a unique ratio of signals from the photodiodes, which allows for the closed-loop operation of the galvo mirror system.

The systems can be driven to scan their full mechanical range of ±12.5° at a frequency of 100 Hz when using a square wave control input voltage or at 350 Hz when using a sine wave. For a single small-angle step of 0.2°, it takes the mirror 300 μs to come to rest at the command position.
The scan frequency range is DC to 1 kHz and the angular resolution is 0.0008° (15 μrad).

 

Small Beam Diameter Galvanometer Systems


* 1D and 2D Scanning Galvo Mirror Systems
* Silver, Gold, Broadband (E02) and High Power Dual Band Coating Options
* Includes 1 or 2 Driver Cards for Single or Dual Mirror Systems, Respectively
* Includes Driver Card Heat Sink(s)
* Power Supply Not Included

 

ABOUT US

Our Mission is to accelerate the advancement of optical technology for precision measurements and their applications from the table tops of research laboratories to standard use in communication and high technology industries. Our aim is to serve our customers. Our hope is to create a place for highly skilled people in an open environment

contact us

Tel               +966 35823441
Fax               +966 35823441
Egypt Mobile  +2 0120 7577664
KSA Mobile     +966 545 991188
Email             This email address is being protected from spambots. You need JavaScript enabled to view it.

newsletter