Aligna beam positioning

Aligna®

Active beam stabilization, alignment, guidance, and beam switching of lasers

Aligna is a complete solution for beam pointing stabilization and/or beam guidance. The control electronics, a combined angle and position detector and two active mirrors form a feedback loop, which suppresses thermal drifts as well as fast fluctuations. This adjusts the beam alignment to submicron accuracy. In addition, the Aligna system offers various algorithms and functionalities such as:

  • Scanning of the beam’s angle and position
  • Optimization of the beam pointing
  • Parallelization of the beam with respect to moving axes
  • Self-learning parameter settings
  • Modular system, control of up to 4 beams
  • All common wavelengths

Why beam stabilization is important

An active beam stabilization system with self-learning parameters reliably prevents beam pointing and also allows active control of beam parameters such as beam diameter, focus position or intensity and polarization properties. Aligna is suitable for all common wavelengths.

The beam stabilization system at a glance

You need laser radiation with exact positioning for consistently high-quality results? External influences can be precisely compensated, such as drift, vibrations, thermics or the presence of moving components (e.g. motorized opto-mechanics). Get to know our Aligna system:

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We deliver your Aligna system as a plug & play kit, fully configured and mounted on an acrylic glass plate. So you can start using the system right away and get to know it before integrating the components into their final application.

Beam sharing, beam switching and stabilization at a glance

An Aligna laser beam-sharing system allows several workstations to be operated with one laser. With beam-sharing (see picture), all work stations can be used independently of each other, since a part of the beam is forwarded to the next work station in each case by a beam splitter. With beam-switching, the laser beam can be changed between different workstations, and the full laser power is then available for the selected application. In this case, the beam splitters indicated in the picture are replaced by beam switches. The possible applications are manifold.

Beam delivery across distances

Whether it’s a matter of millimeters to the next single-mode fiber or 50 meters to the next beamline station, as a beam delivery system with active stabilization, Aligna bridges distances. Even from the earth to outer space.

The basic configuration

A common configuration, for example for stabilizing a single beam, consists of 1 x position sensor, 2 x actuators and 1 x control electronics. The system can be extended with further components. The range of possible components is shown below.

Grundkomponenten eines Aligna-Strahlstabilisierungssystems (Steuerungselektronik nicht abgebildet)
Basic components of a Aligna Beam Stabilization System (Control-Electronic not shown)

Extension possibilities

Aligna systems can be arranged in almost any desired modular way according to application requirements and can be expanded at any time. A system always consists of the basic elements angle/position sensors, control electronics and actuators (beam steering). In addition, the program includes, for example, beam shutters, fiber alignment options and much more. If you have a special request, please do not hesitate to contact us. A large number of components from our program has been developed as a result of customer requests.

The 3 basic components of an Aligna system

2D and 4D beam stabilization at a glance

Instabilities with laser beams can occur in up to four spatial directions: translational (X and Y) and rotational (Φ and θ). Since the motions occur in all directions, both forward and backward, they are sometimes referred to as 4 and 8 degrees of freedom.

Often the degrees of freedom are interdependent. For example, a pure angular drift leads to a combination of angular and positional motion after a longer propagation distance. The longer the beam paths become, the more obvious this dependence becomes.

Instabilities for laser beams can occur in up to four spatial directions: X, Y, Φ, θ.

For example, consider a mirror holder that drifts by 100 µrad due to changes in room temperature. This angular drift leads to a beam deflection of 0.1 mm already after 1m travel distance and 1 mm deflection after 10m travel distance.

To compensate for the combination of angular and positional drift, a combination of positional and angular correction is required. In the example (figure) this is done by a 4D correction using two 2D mirror actuators.

To measure the angular and positional displacement, two 2D sensors are required consequently, one sensor for the X and Y positions and another for the angular positions Φ and θ. A 4D detector, such as the PSD 4D from TEM Messtechnik, conveniently combines both types of sensors in one housing. Based on the sensor data, the Aligna stabilization system is able to independently perform the correction control of the actuators.

To compensate for the combination of angular and positional displacement, a combination of positional and angular correction (4D correction) is required.

The components in detail

Beam-Steering Components (Actuators)

Aligna40 (±Φ, ±θ)
40×40 mm
Motorized Mirror
Manual actuation possible
Reference encoder
1″, 1/2″, 2″ mirror mount

Aligna60 (±Φ, ±θ)
60×60 mm
Motorized Mirror
Manual actuation possible
Reference encoder
1″, 1/2″, 2″ mirror mount

Aligna MoPiA 40/60 (±Φ, ±θ)
60×60 or
40×40 mm
Piezo + Motorized Actuator

Aligna R (±Φ)
Rotation Stage
e.g. for polarization control,
intensity stabilization

Aligna BeamSwitch
Beam switch & shutter
adjustable limits, feedback (encoder in either direction)
beam dia. < 10mm
beam dump, or mirror

Aligna BeamScan HS |1″ | 2″
High stroke* piezo X|Y scanner
*up to 2×100 mrad, 0.5 kHz
for manual- or auto-coupling of fibersOption: manual or motorized SM fiber focussing

Aligna multiDrill
Autofocus and pointing stabilization head

Aligna Lin
Motorized linear stage
7 mm or moremore on request linear travel
Various adapters for opt. components

Aligna Lin w. fiber collimator
Aligna Lin with special optics, e.g. single-mode fiber collimator

One-Inch | Two-Inch Depending on the application, your system is equipped with components in appropriate dimensions, e.g. 1/2″, 1″, 2″ ….

Position and angle sensors

PSD 2D (±X, ±Y)

Position sensitive detector
Individual use or combined for 4D-detection
Δλ: 380 – 1100 nm or othersOther wavelengths down to 180 nm (UV) and up to 2600 nm (IR) can be realized

PSD 4Dc (±X, ±Y, ±Φ, ±θ)
Position & angular sensitive detector
Compact form factor
Δλ: 380 – 1100 nm or othersOther wavelengths down to 180 nm (UV) and up to 2600 nm (IR) can be realized
Accur: < 1 µm, < 1 µrad

PSD 4De (±X, ±Y, ±Φ, ±θ)
Position & angular sensitive detector
Open system, for experimental setupsWorks the same as PSD 4Dc but offers more flexibility for experimental setups
Δλ: 380 – 1100 nm or othersOther wavelengths down to 180 nm (UV) and up to 2600 nm (IR) can be realized
Accur: < 10 nm, < 10 nrad

Control electronics

Two variants are available as control units: µAligna (left image) and Aligna control electronics in the HE-Rack version (right image).

The control unit in combination with a PSD 4D detector and two Aligna60 actuators forms a flexible, fast and highly precise beam position stabilization for laser beams. The system is suitable for (almost) all wavelengths, (almost) any beam diameter and CW and pulsed lasers (with repetition rates >15kHz).

Additional functionalities include:

  • Scan & Search
  • Optimization of beam position
  • Remote control of mirror holders
  • Logging of beam position or other measured variables

µAligna

  • Very compact design (210 x 125 x 90 mm)
  • Fully automatic, high-precision laser beam alignment
  • Compatible with all Aligna system actuators and detectors

Aligna (19″ rack mounting)

  • suitable for 19″ rack mounting (484 x 343 x 150 (3 HU) mm)
  • Fully automatic, high-precision laser beam alignment
  • Compatible with Aligna system actuators and detectors

Depending on your application, our staff will suggest the most suitable variant of the control unit (µAligna or HE-Rack variant).

Stabilization of 1 beam

The 4D stabilization system is the most common application for beam stabilization. The position of the laser spot on the target is to be kept stable. This is (typically) achieved by controlling 2 x active mirrors and by 1 x position & angular sensitive detector.

Application Aligna Single-Beam Stabilization

Stabilization 1 beam over large distance

Similar to 1-beam stabilization, but with additional position control, which simplifies beam search and beam guidance for very long paths. Well suited for beamlines or for beam delivery across laboratories.

Application beam stabilization 1 beam over long distances with 3 actuators

Overlaying 2 or more laser beams

If several beams have to be positioned and kept stable on the same spot, a multi-beam stabilization system is appropriate.

Beam stabilization of 2 beams merged to one target position

Material processing with focus stabilization

Autofocus and point stabilization are the advantages of the “multi-drill” from TEM Messtechnik. It is particularly useful for material processing applications and everywhere where the focus of the laser spot plays a crucial role.

Beam stabilization with auto-focus for materials processing

Focusing to a capillary with beam stabilization

A typical application for Aligna systems is the stabilization of a beam focused into a hollow fiber or capillary using a lens with a relatively long focal length (f = 0.3 m … 2 m).

Automatic single mode fiber coupling

Fast setting of high coupling efficiency is achieved by automatic fiber coupling. Maximum intensity can be achieved and secured at any time. Highly convenient beam coupling is made possible by a scan mode, which allows fast scanning of the fiber input.

Automated fiber alignment for laser beams

Beam switching and beam sharing

Beam switching allows the laser beam to be switched between different workstations, and the (almost) full laser power is available for the selected application. With a beam sharing system, several workstations can be operated simultaneously with one light source.

Beam Switching

Beam guidance with stabilization over lab tables or rooms

The position of the laser spot on the target must be kept stable, even if the laser source and application are located on different tables. Beam stabilization solutions are also suitable for areas with restricted access, e.g. S3 or S4 bio-labs, clean rooms or radioactive areas.

Application Aligna beam stabilization across laboratory benches

Gantry system for one axis

Beam stabilization, precise focus control and beam parallelization along long travel paths are required for common laser material processing systems. Laser beam stabilization in gantry systems where the beam is in motion is a very typical application for Aligna systems.

Application Single-axis gantry with stabilization and beam parallelization

Gantry system for 2 (or 3) axis

As with the gantry application before, but here it is about beam stabilization with moving focusing heads in (at least) two directions, X and Y, and sometimes also in Z.

Application Two & Three-Axis Gantry with Stabilization 1

Typical Aligna System configurations

The following is an overview of typical configurations of an Aligna complete system. The prices are for rough orientation. Ask us for a quote to get binding prices and configuration details.

 

1 beam
      
System configurationHigh rep. with motorsLow rep. with motorsHigh rep. with motors + piezosLow rep. with motors + piezosLow rep. with motors + piezos
Explanationcw or reprate > 3 kHz, slow drifts (low reg. bandwidth)reprate < 3 kHz (sample & hold)same as before + fast actuators (reg. bandwidth up to 1 kHzcombination for low reprate and fast actuatorscombination for low reprate and fast actuators; for very long distances
Config. NameMoA HiRepMoA LoRepMoPiA HiRepMoPiA LoRepMoPiA LoRep BeamLine
Single item price*
Aligna 19" Rack111112,690
SPM-base11111980
SPM-P111390
SPM-SH111285
µStpDriver11112490
Piezo Driver111620
PSD 4Dc/e111111,470
Aligna 60 MoPiA221,980
Aligna 60 MMM2231,580
BS One Inch975
BS Two Inch2995
AimPD1173
Total system price* in EUR8,7909,07510,60010,88514,278
* Prices are a rough estimation without discount, cables, installation, shipping, adaption, specials, etc.
8% surcharge for non-European countries plus shipping and if applicable import duty/taxes in the country of destination apply

 

2 beams     
High rep. with motorsLow rep. with motorsHigh rep. with motors + piezosLow rep. with motors + piezos
Explanationcw or reprate > 3 kHz, slow drifts (low reg. bandwidth); 2 indep. beams or 2 partial beams of an amplified chainreprate < 3 kHz (sample & hold) for 2 beamssame as before + fast actuators (reg. Bandwidth up to 1 kHz, for 2 beamscombination for low reprate and fast actuators for 2 beams
Config. NameMoA HiRep 2BMoA LoRep 2BMoPiA HiRep 2BMoPiA LoRep 2B
Single item price*
Aligna 19" Rack11112,690
SPM-base2222980
SPM-P22390
SPM-SH22285
µStpDriver2222490
Piezo Driver2222620
PSD 4Dc/e22221,470
Aligna 60 MoPiA441,980
Aligna 60 MMM441,580
BS One Inch975
BS Two Inch995
AimPD173
Total system price EUR*14,89015,46017,89018,460
* Prices are a rough estimation without discount, cables, installation, shipping, adaption, specials, etc.
8% surcharge for non-European countries plus shipping and if applicable import duty/taxes in the country of destination apply

Active vs. Passive Stability

Smart Aligna Electronics Outperforms Steel

An introduction of Aligna

Presented by Market Tech Inc., official TEM distributor in USA