Luna MDL-002 motorized variable optical delay line module
Luna / Optical Delay Control Modules / Free Space
MDL-002

VariDelay II MDL-002 Motorized Variable Optical Delay Line Module

Fiber-coupled motorized free-space optical delay line with up to 560 ps single-pass delay and 1 fs (0.3 µm) resolution per encoder count.

Center wavelengths (λc)
SM, single pass: 1310/1550 dual window, 1060, or 840nm; SM, double pass: 1310 or 1550nm; PM, single pass: 1310, 1550, 1060, or 840nm
Wavelength range
λc ±50nm
Operating wavelength
SM: 1260 to 1650 nm
Operating wavelength
PM or double-pass: 1310 ± 50 or 1550 ± 50 nm
Datasheet

Overview

The Luna MDL-002 (VariDelay II) is a fiber-coupled motorized variable optical delay line in which the delay adjustment path is in free space. It is driven by a DC motor with an integrated encoder and provides optical path length adjustment of up to 560 ps in single-pass configuration, or 1120 ps in the double-pass model, with scan speeds of up to 256 ps/s. The delay resolution is 0.3 µm (1 fs) per encoder count in single pass.

Configurations

Three configurations are available: an integrated unit for bench-top laboratory use, a two-piece unit with the optical head and control unit separated for installation into other equipment, and an OEM version in which the control unit is replaced by a miniature controller board. All three versions can be remote controlled by a PC or microprocessor via RS-232. The standard controller unit also has an integrated keypad and LCD display; the OEM board has no display and is controlled by RS-232 only.

Fiber and wavelength options

The delay line is available with either single mode or PM (Panda) fiber pigtails, at center wavelengths of 840, 1060, 1310 or 1550 nm, or as a dual-window 1310/1550 nm SM single-pass device. The 1120 ps model is a double-pass device in which input and output signals travel on the same pigtail; a circulator or PBS can be used to separate them. Double-pass versions are not available for 840 or 1060 nm.

Use

The MDL-002 is suited to optical path adjustment of up to several centimeters, for example in optical coherence tomography (OCT) and other interferometric systems, multichannel path matching in laser systems, and network optical length control and timing alignment. It can be combined with a fiber stretcher or phase shifter for coarse and fine delay adjustment.

Key Features

  • Long delay range: up to 560 ps single pass, 1120 ps double pass
  • Multiple controller configurations: integrated, remote head with standard controller, remote head with mini controller board
  • Scan speed up to 256 ps/s
  • Compact
  • High resolution: 0.3 µm or 1 fs per encoder count (single pass)
  • Low backlash
  • Low insertion loss
  • High stability
  • DC motor with integrated encoder
  • RS-232 remote control on all versions
  • Integrated keypad and LCD display on standard controller
  • Single mode or PM fiber pigtails

Specifications

Optical
Center wavelengths (λc) SM, single pass: 1310/1550 dual window, 1060, or 840nm; SM, double pass: 1310 or 1550nm; PM, single pass: 1310, 1550, 1060, or 840nm
Wavelength range λc ±50nm
Operating wavelength
SM
 SM: 1260 to 1650 nm
Other wavelengths available upon request
Operating wavelength
PM, Double-pass
 PM or double-pass: 1310 ± 50 or 1550 ± 50 nm
Operating wavelength 840±50nm or 1060 ± 50nm
Double-pass versions not available for 840 or 1060nm
Optical delay range
330 ps model
 0 – 330 ps
Single-pass model
Optical delay range
560 ps model
 0 – 560 ps
Single-pass model
Optical delay range
1120 ps model
 0 – 1120 ps
Double-pass model; input and output signals travel on the same pigtail
Optical delay resolution 0.3 µm or 1 fs per encoder count (single-pass)
Optical delay resolution
1120 ps model
 0.6 µm or 2 fs per encoder count (double-pass)
Scan speed up to 256 ps/s
Insertion loss 1.0 dB nominal (1310/1550nm single pass)
Valid over ±50nm range for a device without connectors at 23±5°C
Insertion loss 1.5 dB nominal (840nm or 1060nm single pass)
Valid over ±50nm range for a device without connectors at 23±5°C
Insertion loss
1120 ps model
 1.5 dB nominal (1310 or 1550nm double pass)
Valid over ±50nm range for a device without connectors at 23±5°C
Insertion loss variation over delay range
330 ps model
 ±0.3 dB over entire range for 330 ps model
Insertion loss variation over delay range
560 ps model
 ±0.5 dB over entire range for 560 ps model
Insertion loss variation over delay range
1120 ps model
 ±0.7 dB (1120 ps model)
Return loss 50 dB
Extinction ratio
PM
 > 18 dB for PM model
Optical damage power threshold 300 mW
Fiber type
1060 nm
 HI1060 or PM Panda (1060 nm)
Mechanical
Mechanical position accuracy ±3 µm (single-pass)
Given for mechanical position of reflector at static position setting
Mechanical position accuracy
1120 ps model
 ±6 µm (double-pass)
Datasheet value; the web page lists ±3µm double pass
Mechanical position repeatability ±3 µm (single-pass)
Given for mechanical position of reflector at static position setting
Mechanical position repeatability
1120 ps model
 ±6 µm (double-pass)
Datasheet value; the web page lists ±3 µm double pass
Control and Power
Power supply 12 VDC / 1A max.
Control mode Panel keypad and RS-232 interface
For model with standard control unit; OEM board has no display and is controlled by RS-232 only
Display 2 x 16 character LCD
For model with standard control unit
Environmental
Operating temperature 0 °C to 40 °C
Storage temperature -20 °C to 60 °C
Physical
Dimensions (control unit/integrated version)
560 ps model, 1120 ps model
 9" (L) × 4.4" (W) × 1.6" (H)
560 ps or 1120 ps models
Dimensions (mini controller board)
O = Remote head/mini controller board
 2.56" (L) × 2.56" (W) × 0.85" (H)

Specifications are taken from the manufacturer's documentation. See the datasheet for complete and current values.

Applications

  • Optical coherence tomography (OCT)
  • Interferometric systems
  • Multichannel path matching in laser systems
  • Network optical length control and timing alignment
  • Optical Fourier spectrum analysis
  • Optical interferometry
  • Delay generation and measurement
  • Optical time division multiplexing (OTDM)
  • Fiber sensors
  • Coarse delay adjustment combined with a fiber stretcher or phase shifter

Options & Accessories

Option Description
84 Wavelength: 840nm
10 Wavelength: 1060 nm
13 Wavelength: 1310 nm
15 Wavelength: 1550 nm
35 Wavelength: 1310 & 1550 nm — Dual window 1310/1550nm, available only for SM single-pass devices (330 and 560 ps)
33 Delay range: 330 ps
56 Delay range: 560 ps
11 Delay range: 1120 ps — Double-pass; not available for 840 or 1060nm
SS Fiber type: SM
PP Fiber type: PM Panda
I Configuration: integrated
D Configuration: remote head/standard controller
O Configuration: remote head/mini controller board
NC Connector type: no connectors — Other options: FC/PC, FC/APC, SC/PC, SC/APC, or others specify

Documents & Resources

MDL-002 Data Sheet
datasheet
MDL-002 User Guide (Standard Configuration)
manual
MDL-002 User Guide (OEM Configuration)
manual
FAQs
other
MDL-002 Data Sheet
datasheet · PDF