DVA - Diffractive Variable Beam Attenuator

Diffractive attenuators control the power of laser radiation using diffraction gratings. Since phase diffraction gratings do not absorb light they can be used to attenuate also high-power laser radiation (cw, pulsed). Variation of grating parameters along the attenuator results in variable transmission at a given wavelength. Diffractive attenuators can be designed for deep UV till IR.

Description 

Principle of operation

Light beam passing through a diffractive grating is partially deflected into several diffractive orders which are blocked by diaphragm. Subsequently zero order beam along optical axis is attenuated. The diffraction efficiency and thus the intensity of output radiation Iout depends on the grating parameters. With variation of the grating parameters along the attenuator the transmission changes from Tmax to Tmin by 340° rotation of attenuator wheel (with T= Iout/Iin). Although diffractive attenuators are optimized for its design wavelength λ0, they will operate over a larger spectral range (λ0 ±15%) with minor attenuation range decreasing. The functional dependence of transmission function -e.g. its linearity- remains the same. Notice that the attenuator works also at λ0/3 of design wavelength, but has nearly zero effect at λ0/2.

Design and Operation

Attenuator includes grating wheel mounted in a special encapsulated housing with entrance and exit tubes. Housing and tubes are intended for blocking parasitic diffractive orders and absorbing of laser radiation. Tubes are suitable for less than 20Watt average power dissipation. Special finned radiators are required for higher laser power.

Order information

Each attenuator set includes attenuator disc within encapsulated housing, 2 radiator tubes (for blocking of diffracted light at entrance-/exit beam ports)

Design wavelength λ0(also suitable for λ0/3) Cat.-No.
1064nm (355nm*) DVA1064
800nm (266nm*) DVA0800
532nm DVA0532
355nm DVA0355
others wavelength on request 

* reduced transmission range

Specifications 
Model DVA
Substrate material UV grade fused silica (UVFS)
Surface flatness, wedge  λ/4 @ 532 nm over clear aperture, ≤ 30arcsec
Diameter / thickness quartz substr. 60 mm, 3 mm
Width grating area / cear aperture  15 mm / 14 mm (12 mm with tubes)
Front side  2-dimensional binary phase grating
Back side AR-coating, R(l0) < 0.3% (effective for design wavelength)
Transmission range  Tlinear ≥ 2% – 96% over 340°(deviation from linearity ≤ 5%)
Damage threshold ≥ 500W/cm²-cw
≥ 3J/cm²with 10ns pulses
≥ 1J/cm²with 150fs pulses (800nm, 1kHz)
Documents 
International Distributors 

Our beam shaping optics are also available at the following international distributors:

 

Eastern Europe:

EKSMA Optics

Mokslininku str. 11,
Vilnius, LT-08412, Lithuania
Phone: +370 5 272 99 00
Fax: +370 5 272 92 99
E-mail: info@eksmaoptics.com

 

Japan:

Tokyo Instruments

6-18-14 Nishikasai Edogawa-ku,
Tokyo 134-0088, Japan
Phone: +81 3 3686 4711
Fax: +81 3 3686 0831
E-mail: sales@tokyoinst.co.jp

 

North America:

CourierTronics

315 Carrolls Grove Rd
Troy, NY 12180, USA
Phone: +1 518 279 9500
Fax: +1 518 279 3864
E-mail: info@couriertronics.com

Inquiry 
Do you have questions about DVA?
Your details will be gathered and handled to respond to your request.
Detailed information on this topic can be retrieved from our privacy policy.
  • Description
  • Specifications
  • Pictures
  • Documents
  • International Distributors
  • Inquiry

Principle of operation

Light beam passing through a diffractive grating is partially deflected into several diffractive orders which are blocked by diaphragm. Subsequently zero order beam along optical axis is attenuated. The diffraction efficiency and thus the intensity of output radiation Iout depends on the grating parameters. With variation of the grating parameters along the attenuator the transmission changes from Tmax to Tmin by 340° rotation of attenuator wheel (with T= Iout/Iin). Although diffractive attenuators are optimized for its design wavelength λ0, they will operate over a larger spectral range (λ0 ±15%) with minor attenuation range decreasing. The functional dependence of transmission function -e.g. its linearity- remains the same. Notice that the attenuator works also at λ0/3 of design wavelength, but has nearly zero effect at λ0/2.

Design and Operation

Attenuator includes grating wheel mounted in a special encapsulated housing with entrance and exit tubes. Housing and tubes are intended for blocking parasitic diffractive orders and absorbing of laser radiation. Tubes are suitable for less than 20Watt average power dissipation. Special finned radiators are required for higher laser power.

Order information

Each attenuator set includes attenuator disc within encapsulated housing, 2 radiator tubes (for blocking of diffracted light at entrance-/exit beam ports)

Design wavelength λ0(also suitable for λ0/3) Cat.-No.
1064nm (355nm*) DVA1064
800nm (266nm*) DVA0800
532nm DVA0532
355nm DVA0355
others wavelength on request 

* reduced transmission range

Model DVA
Substrate material UV grade fused silica (UVFS)
Surface flatness, wedge λ/4 @ 532 nm over clear aperture, ≤ 30arcsec
Diameter / thickness quartz substr. 60 mm, 3 mm
Width grating area / cear aperture 15 mm / 14 mm (12 mm with tubes)
Front side 2-dimensional binary phase grating
Back side AR-coating, R(l0) < 0.3% (effective for design wavelength)
Transmission range Tlinear ≥ 2% – 96% over 340°(deviation from linearity ≤ 5%)
Damage threshold ≥ 500W/cm²-cw
≥ 3J/cm²with 10ns pulses
≥ 1J/cm²with 150fs pulses (800nm, 1kHz)

Our beam shaping optics are also available at the following international distributors:

 

Eastern Europe:

EKSMA Optics

Mokslininku str. 11,
Vilnius, LT-08412, Lithuania
Phone: +370 5 272 99 00
Fax: +370 5 272 92 99
E-mail: info@eksmaoptics.com

 

Japan:

Tokyo Instruments

6-18-14 Nishikasai Edogawa-ku,
Tokyo 134-0088, Japan
Phone: +81 3 3686 4711
Fax: +81 3 3686 0831
E-mail: sales@tokyoinst.co.jp

 

North America:

CourierTronics

315 Carrolls Grove Rd
Troy, NY 12180, USA
Phone: +1 518 279 9500
Fax: +1 518 279 3864
E-mail: info@couriertronics.com

Do you have questions about DVA?
Your details will be gathered and handled to respond to your request.
Detailed information on this topic can be retrieved from our privacy policy.

Do you have questions about our products?

Write to us | info@topag.de

Give us a call | +49 6151 42944 0

TOPAG Lasertechnik GmbH
Nieder-Ramstädter Str. 247
64285 Darmstadt, Germany
Phone: +49 6151 42944 0
Fax: +49 6151 42944 11
E-mail: info@topag.de