THORLABS OCTP Series User manual

OCTP Series and OCT-LKx
User-Customizable Scanner
and Scan Lens Kits
User Manual

Original User Manual – not translated

OCTP Series Scanner
Table of Contents
Chapter 1Warning Symbol Definitions.........................................................................................1
Chapter 2Introduction.....................................................................................................................2
2.1.Safety.......................................................................................................................... 2
2.2.Care and Maintenance .............................................................................................. 3
2.2.1.Optical Cleaning .............................................................................................................. 3 
2.2.2.Service ............................................................................................................................ 3
2.2.3.Accessories and Customization ...................................................................................... 3
Chapter 3Components and Compatibility...................................................................................4
3.1.Components .............................................................................................................. 4
3.1.1.Fiber Collimation Module ................................................................................................ 5
3.1.2.Optical Beamsplitter Module (not for OCTP-NR) ............................................................ 5
3.1.3.Reference Arm Module (not for OCTP-NR) .................................................................... 6
3.1.4.OCT Scan Cube Module ................................................................................................. 7
3.1.5.Objective Holders ............................................................................................................ 8
3.1.6.Lens Kits .......................................................................................................................... 9
3.1.7.OCT-STAND ................................................................................................................... 9
3.2.Custom Mounting.................................................................................................... 10
3.2.1.Threaded Holes on Imperial OCTP Scan Cube Module ............................................... 10
3.2.2.Threaded Holes on Metric OCTP Scan Cube Module .................................................. 11
3.2.3.Mounting to Thorlabs OCT-STAND .............................................................................. 11
3.3.Compatibility between Scanner and Base Units .................................................. 12
Chapter 4Installation.....................................................................................................................13
4.1.OCTP Mounting ....................................................................................................... 14
4.2.OCTP Connections.................................................................................................. 15
4.2.1.Connecting the Electrical Control Interface ................................................................... 15
4.2.2.Connecting the Optical Fiber......................................................................................... 16
4.3.Optical Alignment.................................................................................................... 17
4.3.1.Alignment to Optical Axis .............................................................................................. 17
4.3.2.Polarization Adjustment ................................................................................................ 21
Chapter 5Description....................................................................................................................24
5.1.Theory ...................................................................................................................... 24
5.1.1.Signal Generation ......................................................................................................... 24
5.1.2.Limitations ..................................................................................................................... 24
5.2.Optical Design ......................................................................................................... 25
5.2.1.Common Path Setup (OCTP) ....................................................................................... 25
5.2.2.Dual Path Setup (OCTP-NR) ........................................................................................ 25
5.3.Intended Use............................................................................................................ 26
5.3.1.Realization..................................................................................................................... 26
Chapter 6Troubleshooting...........................................................................................................29
Chapter 7Certifications and Compliance...................................................................................30
Chapter 8Specifications...............................................................................................................31
8.1.Reflectivity Scanning Mirror................................................................................... 32
8.2.Transmission Unscanned Optional Port............................................................... 32
Chapter 9Warranty........................................................................................................................33

OCTP Series Scanner
9.1.Imaging Systems..................................................................................................... 33
9.2.Non-Warranty Repairs ............................................................................................ 33
9.3.Warranty Exclusions............................................................................................... 33
Chapter 10Regulatory.....................................................................................................................34
10.1.Waste Treatment is Your Own Responsibility...................................................... 34
10.2.Ecological Background .......................................................................................... 34
Chapter 11Thorlabs OCT Support Contact..................................................................................35
Chapter 12Thorlabs Worldwide Contacts....................................................................................36

OCTP Series Scanner Chapter 1: Warning Symbol Definitions
Rev F, November 03, 2018 Page 1
Chapter 1 Warning Symbol Definitions
Below is a list of warning symbols you may encounter in this manual or on your device.
Symbol Description
Direct Current
Alternating Current
Both Direct and Alternating Current
Earth Ground Terminal
Protective Conductor Terminal
Frame or Chassis Terminal
Equipotentiality
On (Supply)
Off (Supply)
In Position of a Bi-Stable Push Control
Out Position of a Bi-Stable Push Control
Caution: Risk of Electric Shock
Caution: Hot Surface
Caution: Risk of Danger
Warning: Laser Radiation
Caution: Spinning Blades May Cause Harm

OCTP Series Scanner Chapter 2: Introduction
Page 2 MTN003971
Chapter 2 Introduction
2.1. Safety
Please read this manual carefully before operating the OCTP. Please also read any manuals for the systems
being connected to the OCTP.
All statements regarding safety and technical specifications will only apply when the unit is operated correctly.
ATTENTION
This equipment is intended for laboratory use only and is not certified for medical applications,
including, but not limited to, life support situations.
WARRANTY WARNING
There are sensitive electronic and optical parts in the OCTP.
Any modification or servicing of this system by unqualified personnel renders Thorlabs free of
any liability.
Any modification of the galvanometer scanners or the camera may cause loss of the factory
optical alignment.
This device can only be returned for service when it is packed into the complete original
packaging, including all foam packing inserts. Please contact Thorlabs’ OCT support
(see Chapter 11) for replacement packaging if the original packaging has been lost.
LASER RADIATION WARNING
When a light source (e.g. SLD, laser) is being coupled into the OCTP, please observe the
appropriate laser safety precautions for your own protection. The appropriate laser safety
precautions depend on the light source coupled into the OCTP.
During normal operations, laser light will be present within the scanner and will also be emitted
from the scanner. Laser light may also be emitted from unexpected locations, such as if the fiber
has been disconnected from the body or if the reference arm has been disconnected.
In addition, the OCTP is an optical system that can influence the divergence of the beam. This
can cause a change of laser class of the light source, especially if the OCTP is used without an
objective.
Always turn off the light source before changing or adjusting the OCTP configuration or
accessories as the objective, scan lens kit, or sample z-spacer. For Thorlabs OCT base units,
turn off the OCT base unit main power to turn off the light source.

OCTP Series Scanner Chapter 2: Introduction
Rev F, November 03, 2018 Page 3
2.2. Care and Maintenance
The system should be treated with care, particularly during transportation and unpacking. Hitting or dropping
the system can damage the unit and lower system performance. If mishandling occurs, misalignment of the
optical components may occur, leading to a decrease in image quality. In this situation, the system should be
realigned by qualified personnel.
 Do not store or operate in a damp, closed environment.
 Do not store or operate on surfaces that are susceptible to vibrations.
 Do not expose to direct sunlight.
 Do not use solvents on or near the equipment.
 Keep the unit away from dust, dirt, and airborne contaminants, such as cigarette smoke. The system is
not designed for outdoor use. Protect the equipment from rain, snow, and humidity.
 Do not subject the equipment to mechanical and thermal extremes. Protect the equipment from rapid
variations in temperature.
 Handle all electrical and fiber connectors with care. Use of excessive force to form electrical or fiber
connections may damage the connectors.
2.2.1. Optical Cleaning
The most common cause of low signal intensity is dirtying of the fiber due to airborne contaminants. To minimize
the fiber’s exposure to air, avoid unnecessary disconnections of the optical fiber patch cable. Ensure that the
connection is tight, and keep the fiber as straight as possible without placing it under tension. It is also advisable
to check the fiber when making other adjustments to the optical system, such as changing the objective.
Thorlabs’ Fiber Inspection Scope (Item # FS201) can help determine when the fiber needs cleaning. We
recommend our Fiber Connector Cleaner (Item # FBC1) for quickly cleaning the fiber tips.
2.2.2. Service
Only trained and approved Thorlabs personnel are allowed to service the system. Please contact Thorlabs’
OCT support (see Chapter 11) for more information.
2.2.3. Accessories and Customization
The OCTP series user-customizable scanners are Thorlabs-qualified accessories for Thorlabs’ OCT Systems
(i.e., Callisto, Ganymede, Telesto, and Vega). In addition to enabling typical imaging applications, the OCTP
scanners effectively connect our SM1 lens tubes and 30 mm cage systems to our OCT systems, enabling
custom applications. We strongly suggest using Thorlabs’ scan lens objectives or OCT-LKx scan lens kits with
the OCTP scanners, as they were specifically designed to work together.
In order to achieve the intended performance, this scanner should only be used with qualified parts. Please hold
a conversation with Thorlabs’ OCT support (see Chapter 11) to determine if other parts you wish to use are
compatible. Any modification or servicing of this system by unqualified personnel renders the warranty null and
void, leaving Thorlabs free of any liability.

OCTP Series Scanner Chapter 3: Components and Compatibility
Page 4 MTN003971
Chapter 3 Components and Compatibility
3.1. Components
The OCTP is intended as an accessory for use with Thorlabs OCT base units. It is assembled from standard
Thorlabs opto-mechanics that provide mechanical compatibility with our 30 mm cage systems, SM1 lens tubes,
and Ø1” optics, providing a high degree of experimental flexibility.
The major components of the scanner, illustrated in Figure 1 below, include: a fiber collimation module, optical
beamsplitter module, reference arm module, and an OCT scan cube module.
These are described in the following sections.
Figure 1 OCTP Modules Common Path
ATTENTION
Always turn off the light source before changing or adjusting OCTP configuration or accessories
such as the objective, scan lens kit, reference arm adapter, or sample z-spacer. For Thorlabs
OCT base units, turn off the OCT base unit main power to turn off the light source.

OCTP Series Scanner Chapter 3: Components and Compatibility
Rev F, November 03, 2018 Page 5
3.1.1. Fiber Collimation Module
Figure 2 Fiber Collimation Module with Built-In Fiber Collimator
The fiber collimation module has a built-in fiber collimator with 25 mm focal length. The 2.0 mm narrow key
FC/APC receptacle is centered within a kinematic mirror mount, which adapts the fiber port to our 30 mm cage
system.
The cage compatible design enables the use of different beam diameters and collimator focal lengths, although
the clear aperture of the scanner set is limited to Ø6 mm.
3.1.2. Optical Beamsplitter Module (not for OCTP-NR)
Figure 3 Optical Beam Splitter Module
The optical beamsplitter module consists of a non-polarizing cube beamsplitter that is mounted inside a 30 mm
cage cube. This cage cube is secured to a lockable rotation mount. The cube beamsplitter’s length, width, and
height are 20 mm.
The 30 mm cage cube has four ports, one of which is blocked by an end cap before being shipped. In principle,
it is possible to use this last port for asymmetric light coupling, a second detector, or a second input wavelength.
Please contact Thorlabs’ OCT support (see Chapter 11) for details.

OCTP Series Scanner Chapter 3: Components and Compatibility
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3.1.3. Reference Arm Module (not for OCTP-NR)
Figure 4 Reference Arm Module
The reference arm module contains a mounted mirror (i.e., retroreflector) that reflects the beam from the light
source back into the OCT interferometer.
In order to match the optical path length in this reference arm to the optical path length of the light from the
sample, it may be necessary to translate the mirror along the axis of the 30 mm cage system. Coarse length
adjustments can be performed by loosening the top cage plate or the variable lens tube. Fine adjustments of
the reference length can be performed by moving the retro reflector: ±2 mm (total range of 4 mm) for the OCTP
with the non-rotating zoom housing and 12.7 mm for the linear stage of the OCTP-PS.
In order to adjust the reference arm intensity, a zero-aperture iris is located in front of the mirror.
For objective-dependent dispersion compensation, a holder hosting a compensation glass sample is included.
The 30 mm cage system makes it easy to add optomechanical and optical components to the reference arm.
For instance, windows for group velocity dispersion (GVD) compensation can be mounted in this arm, as can
optical filters.

OCTP Series Scanner Chapter 3: Components and Compatibility
Rev F, November 03, 2018 Page 7
3.1.4. OCT Scan Cube Module
Figure 5 OCT Scan Cube Module
The OCT scan cube module provides high-speed, two-dimensional (X and Y) raster scans of the specimen. The
clear aperture of the scan mirrors used within is Ø6 mm. The module also contains a high-resolution video
camera for recording the sample during the measurement.
The electrical control interface hosts the included Thorlabs electric control cable to connect the imaging scanner
with a Thorlabs OCT base unit. Please contact Thorlabs’ OCT support (see Chapter 11) for information
regarding the pin configuration.
Should the user wish to view the direct, non-descanned output of the objective (i.e., by passing the primary
scan mirror, transmitting the visual wavelength range), the top of the scan cube contains an output port with a
removable end cap (Item # SM1CP2). This port can be used for different imaging modalities or additional
sample illumination. Unscrewing the end cap exposes an internal SM1 (1.035"-40) threading, which is
surrounded by four 4-40 taps that are compatible with our 30 mm cage systems.
A transmission graph of this scan mirror is given in Figure 35.
ATTENTION
Use of the direct output port requires removal of the camera. In addition, a hot mirror with a 2.5 mm
circular aperture could be removed. Please contact Thorlabs’ OCT support (see Chapter 11) for details.

OCTP Series Scanner Chapter 3: Components and Compatibility
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3.1.5. Objective Holders
There are two different brass plates included that are used to hold the objective to the OCTP:
 The pre-installed objective holder for the use of our OCT-LKx scan lens kits.
For an OCTP scanner ordered with a scan lens kit, it is pre-installed. These kits include a telecentric
scan lens (Item # LSM02, LSM02-BB, LSM03, LSM03-BB, LSM04, or LSM04-BB) and a matched
sample illumination light conductor.
Figure 6 Objective Holder for OCT-LKx Scan Lens Kits or M25-Threaded Objectives
 Alternatively, another brass plate with internal SM1 (1.035”-40) threads and four 4-40 tapped holes for
our 30 mm cage systems is included.
Figure 7 Objective Holder for SM1-Threaded Optomechanics and 30 mm Cage System
ATTENTION
The illumination of the pre-installed objective holder for OCT-LKx Scan Lens Kits is connected
to a power supply.
When changing the brass plates this connection must be disconnected using the internal
electric plug.

OCTP Series Scanner Chapter 3: Components and Compatibility
Rev F, November 03, 2018 Page 9
3.1.6. Lens Kits
For the case that an OCT scan lens kit is installed, the mechanical dimensions are summarized in the table
below.
Figure 8 Objective Holder Shown with Scan Lens Kit Installed
OCT Scan Lens Kit OCT-LK2(-BB) OCT-LK3(-BB) OCT-LK4(-BB)
Field of View 6 mm x 6 mm 10 mm x 10 mm 16 mm x 16 mm
Barrel Height (B) 29.5 mm 28.0 mm 41.0 mm
Working Distance (WD) 3.4 mm 24.9 mm 41.6 mm
Table 1 Dimensions for OCT-LKx Scan Lens Kits
Changing the objective of the OCTP requires changing the probe configuration data in the software package
ThorImage®OCT. The length of the reference arm must be aligned to match the optical path in the sample arm
as well.
This is performed automatically using the built-in calibration procedure of the ThorImage®OCT software package
version 4.1.4 and higher. A detailed description of this procedure is given in the ThorImage®OCT operating
manual.
3.1.7. OCT-STAND
The OCT-STAND is a dedicated stand for OCTP scanners. The OCTP scanners are attached to the focus block
of the OCT-STAND using a spring-loaded mount accepting the dovetail mount of the OCTP. The focus block
can be rotated 360° around the Ø1.5” rod, and features 30 mm of travel with fine and coarse adjustment knobs.
Figure 9 OCTP in Thorlabs OCT-STAND

OCTP Series Scanner Chapter 3: Components and Compatibility
Page 10 MTN003971
3.2. Custom Mounting
The mechanical drawings shown below depict several threaded holes that can be used to secure the scanner
to an optical breadboard or an application-specific mount. The tap depth is twice the diameter.
3.2.1. Threaded Holes on Imperial OCTP Scan Cube Module
Figure 10 Drawing of Threaded Holes in an Imperial OCTP Scan Cube Module

OCTP Series Scanner Chapter 3: Components and Compatibility
Rev F, November 03, 2018 Page 11
3.2.2. Threaded Holes on Metric OCTP Scan Cube Module
Figure 11 Drawing of Threaded Holes in a Metric OCTP Scan Cube Module
3.2.3. Mounting to Thorlabs OCT-STAND
The OCTP ships with a mounting adapter and a dovetail mount, as shown in Error! Reference source not
found.. These accessories allow the scanner to be mounted to a Thorlabs OCT-STAND which ensures that the
objective is directly centered above the sample plate.
Figure 12 Scanner Mounting Adapter for the OCTP

OCTP Series Scanner Chapter 3: Components and Compatibility
Page 12 MTN003971
3.3. Compatibility between Scanner and Base Units
The OCTP User-Customizable Scanner is a standalone, preassembled, integrated scanner intended for use
together with a Thorlabs OCT base unit.
This scanner is available in versions for different wavelength ranges.
 The OCTP-900 for OCT systems working in the 900 nm regime (i.e., Ganymede or Callisto).
 The OCTP-1300, OCTP-1300NR, and the OCTP-1300PS for OCT systems working in the 1300 nm
regime (i.e., Telesto or Vega).
In this manual we will use abbreviations for the OCTP scanner as follows:
 OCTP OCTP-900, OCTP-1300, OCTP-1300NR, or OCTP-1300PS
 OCTP-PS OCTP-1300PS
 OCTP-NR OCTP-1300NR
All these scanners are also available in a version with metric threads for interface. The part number of these
devices is followed by a separated “M”, e.g. OCTP-900/M.
For common statements, the abbreviation “OCTP” is used for all setups.
The OCTP scanners are fully compatible with all Thorlabs OCT base units of the Callisto, Ganymede, and
Telesto series. The OCTP-NR scanner is intended to be used with the Vega series base units.
The table below gives a short overview of the different user-customizable scanners, their usable wavelength
range and lists preferred OCT base units.
Standard
Scanner
Wavelength
Range
Fiber
Receptacle
Single Mode Fiber OCT Base
Unit
OCTP-900 800 nm – 1000 nm FC/APC Nufern 780 CALxxx
GANxxx
OCTP-1300 1200 nm – 1400 nm FC/APC Corning SMF28 Ultra
or Corning HI-1060
TELxxx
OCTP-1300PS 1200 nm – 1400 nm FC/APC
(Narrow Key)
Corning
PANDA PM13-U25A
Key Aligned to Slow Axis
(Included in Base Unit)
TELxxxPS
OCTP-1300NR 1200 nm – 1400 nm FC/APC Corning SMF28 Ultra VEGxxx
Table 2 Usable Wavelength Range of OCT Scanner
The optical component with the most significant wavelength dependency is a mirror mounted on the Y-axis
galvanometric scanner of the scanner set. A reflectivity graph of the scanning mirror is given in Figure 34.
Detailed information about the spectral performance of the different mirrors are available upon request. Please
contact Thorlabs’ OCT support (see Chapter 11) for details.

OCTP Series Scanner Chapter 4: Installation
Rev F, November 03, 2018 Page 13
Chapter 4 Installation
Figure 13 OCTP
Figure 14 OCTP-PS
The OCTP(-PS) scanner is a preassembled, integral accessory to an OCT base unit. It should be securely
mounted to an optical table or breadboard with minimal vibrations. We recommend mounting the OCTP(-PS) in
a Thorlabs OCT-STAND. The OCTP-PS is composed of a linear stage instead of the lens tube system used in
the OCTP. Hence, adjustments of the reference length are possible. In addition, it consists of two quarter-wave
plates in the sample arm and the reference arm to adjust the polarization state.

OCTP Series Scanner Chapter 4: Installation
Page 14 MTN003971
4.1. OCTP Mounting
To mount the OCTP in the OCT-STAND, gently slide the dovetail of the OCTP into the slide of the OCT-
STAND.
Figure 15 Mounting the OCTP in the OCT-STAND

OCTP Series Scanner Chapter 4: Installation
Rev F, November 03, 2018 Page 15
4.2. OCTP Connections
4.2.1. Connecting the Electrical Control Interface
Attach the electric control cable from the OCT base unit to the OCTP. You may use either side of the cable
since the plugs are identical. The OCTP’s electrical control interface is located at the top of the scan cube, as
shown in Figure 16. Align the red dot of the plug to the alignment mark of the port.
Figure 16 Installation of the Electrical Control Connector at the OCTP
Next, attach the remaining plug of the electrical connection cable to the base unit. The connection is located at
the rear of the base unit, as shown in Figure 17. For installation, align the red dot upwards, facing the alignment
mark in the base unit. Push the connector into the plug marked “Control” until a “click” sound is heard. This click
indicates that the connector is locked.
Figure 17 Installation of the Electrical Control Connector at the Base Unit