THORLABS VEGA Series User manual

SS-OCT Base Unit
Swept Source OCT Systems:
Vega™and Atria™ Series
Operating Manual

Original User Manual –not translated

Table of Contents
Chapter 1 Introduction................................................................................................................. 1
1.1. Safety....................................................................................................................... 2
1.2. Care and Maintenance ........................................................................................... 3
Optical Cleaning..........................................................................................................4
Fiber Cleaning Using the FBC250..............................................................................4
Service ........................................................................................................................4
Accessories and Customization..................................................................................4
Chapter 2 Setup ............................................................................................................................ 5
2.1. Unpacking............................................................................................................... 5
2.2. System Connections.............................................................................................. 5
Base Unit Connections................................................................................................5
Internal Electrical Connections ...................................................................................6
Electrical Interfaces to Imaging Scanner ....................................................................6
2.3. Optical Interface to Imaging Scanner................................................................... 6
2.4. System Installation................................................................................................. 7
Chapter 3 Description.................................................................................................................13
3.1. Tutorial.................................................................................................................. 13
Theory.......................................................................................................................14
Thorlabs Swept-Source OCT System Technology...................................................15
Nomenclature in OCT imaging..................................................................................17
3.2. SS-OCT Base Unit Components ......................................................................... 19
Base Unit...................................................................................................................19
PC with Graphical User Interface..............................................................................19
SDK...........................................................................................................................19
Imaging Scanner (Accessory)...................................................................................21
OCT-Stand (Accessory)............................................................................................23
Chapter 4 System Operation......................................................................................................25
4.1. Starting the System.............................................................................................. 25
Turning on the Base Unit ..........................................................................................25
Starting the Software.................................................................................................25
4.2. Basic Adjustments............................................................................................... 26
Adjusting the Focus...................................................................................................26
Adjusting the Reference Length................................................................................27
Adjusting Polarization................................................................................................28
Adjusting the Reference Light Intensity and Amplification........................................29
4.3. Advanced Adjustments ....................................................................................... 31
Focus and Choice of Objective Lens........................................................................31
Imaging through Refractive Media............................................................................33
Reflecting Surfaces and Interfaces...........................................................................34
Rough Surfaces ........................................................................................................34
4.4. Shutting Down the System.................................................................................. 34
4.5. Example Images................................................................................................... 35
Chapter 5 Imaging Artifacts.......................................................................................................37
5.1. Saturation and Non-Linearity.............................................................................. 37
5.2. Multiple Scattering ............................................................................................... 38

5.3. Phase Wrapping and Fringe Washout................................................................ 40
5.4. Flipped Image....................................................................................................... 41
5.5. Shadowing............................................................................................................ 42
5.6. Image Distortion by Refractive Media ................................................................ 43
The Group Refraction Index......................................................................................44
Measurement Depth in OCT Systems......................................................................45
Distortions in the Image ............................................................................................46
Chapter 6 Troubleshooting........................................................................................................48
6.1. Changing the Input Fuses ................................................................................... 49
Chapter 7 Certifications and Compliance................................................................................50
7.1. Declaration of Conformity Vega™ Series Base Units....................................... 50
7.2. Declaration of Conformity Atria™ Series Base Units ....................................... 52
Chapter 8 Warranty .....................................................................................................................53
8.1. Lasers and Imaging Systems.............................................................................. 53
8.2. Non-Warranty Repairs ......................................................................................... 53
8.3. Warranty Exclusions............................................................................................ 53
Chapter 9 Specifications ............................................................................................................54
Chapter 10 Mechanical Drawings................................................................................................55
Chapter 11 Regulatory..................................................................................................................56
11.1. Waste Treatment is Your Own Responsibility................................................... 56
11.2. Ecological Background ....................................................................................... 56
Chapter 12 Thorlabs OCT Support Contact...............................................................................57
Chapter 13 Thorlabs Worldwide Contacts.................................................................................58

SS-OCT Base Unit Chapter 1: Introduction
Rev C, December 17, 2021 Page 1
Chapter 1 Introduction
ATTENTION
Please read the instruction manual carefully before operating the OCT base unit. All statements
regarding safety and technical specifications will only apply when the unit is operated correctly.
This equipment is intended for laboratory use only and is not certified for medical applications,
including but not limited to life support situations.
Refer to this manual whenever the following symbols are encountered on the OCT base unit:
Attention symbol indicates that additional information is given in this manual.
Laser Safety symbol indicates that laser radiation is present.
ATTENTION
Check the supply voltage of the system before plugging in the computer. Make sure the
included power cords for the base unit, computer, and monitor are connected to a properly
grounded outlet (100 –240 VAC; 50 –60 Hz).
Transportation and delivery may cause the SS-OCT system to be warm or cool upon receipt.
Please wait for the system to reach room temperature before attempting to operate.
Operate this system on a flat, dry, and stable surface only.
WARRANTY WARNING
Do not open the base unit, imaging scanner or PC. There are no user serviceable parts in this
product. Opening the device will void your warranty. Any modification or servicing of this
system by unqualified personnel renders Thorlabs free of any liability. This device can only be
returned when packed into the complete original packaging, including all foam packing inserts.
If necessary, ask for replacement packaging.
The following symbols are being used on the device:
"ON" (power)
"OFF" (power)
Standby
Protective earth; protective ground

SS-OCT Base Unit Chapter 1: Introduction
Page 2 MTN013142-D02
1.1. Safety
SHOCK WARNING –HIGH VOLTAGE
Before applying power to the system, make sure that the protective conductor of the three-
conductor mains power cord is correctly connected to the protective earth contact of the socket
outlet. Improper grounding can cause electrical shock resulting in severe injury or even death.
Make sure that the line voltage rating agrees with your local supply and that the appropriate
fuses are installed. Fuses should only be changed by qualified service personnel. Contact
Thorlabs for assistance. Do not operate without cover installed. Refer servicing to qualified
personnel.
ATTENTION
Do not obstruct the air-ventilation slots in the computer housing. Do not obstruct air-ventilation
into the bottom of the base unit or out of the exhaust fan on the rear of the unit.
Mobile telephones, cellular phones, or other radio transmitters are not to be used within the
range of three meters of this unit, since the electromagnetic field intensity may exceed the
maximum allowed disturbance values according to IEC 61000-6-1:2005.
The safety of any system incorporating the equipment is the responsibility of the assembler of
the system.
If equipment is used in a manner not specified by the manufacturer, the protection provided by
the equipment may be impaired.
LASER RADIATION WARNING
Laser emission may be emitted
a) from the scan lens of a scanner (intended use)
b) from the back of the base unit when the fiber cap is removed and the fiber disconnected
c) from the output of the fiber when the fiber is not connected to a scanner
Do not look into the optical output when the device is operating. The laser radiation is not
visible to the human eye and can cause serious damage to your eyesight.
The laser class information is also stated on the laser safety labels on the back of the housing.
Example given for class 1M LASER product:
INVISIBLE LASER RADIATION
DO NOT STARE INTO BEAM OR VIEW
DIRECTLY WITH OPTICAL INSTRUMENTS
CLASS 1M LASER PRODUCT
CLASSIFIED ACCORDING TO DIN EN 60825-1:2014

SS-OCT Base Unit Chapter 1: Introduction
Rev C, December 17, 2021 Page 3
1.2. Care and Maintenance
Handle the system with care during transportation and unpacking. Banging or dropping the system can damage
the unit or lower system performance. If the system is mishandled during shipment, the optical components
may become misaligned, which can lead to a decrease in image quality. If this occurs, the system will need to
be realigned by qualified personnel. Please contact Thorlabs’ OCT support (see Chapter 12) for more
information.
•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 away from dust, dirt, and air-borne pollutants (including cigarette smoke). The system is not
designed for outdoor use. Protect the equipment from rain, snow, and humidity.
•Do not expose to mechanical and thermal extremes. Protect the equipment from rapid variation in
temperature.
•Handle all connectors, both electrical and optical, with care. Do not use unnecessary force, as this may
damage the connectors.
•Handle the optical fiber with care. Mechanical stress can decrease performance and potentially destroy
the fiber. Continual bending of the optical fiber can cause damage. It is important, therefore, to keep
the optical fiber patch cable as straight as possible to minimize bending.
Note: The most common cause of low signal intensity is contamination of the fiber due to airborne pollutants.
To minimize exposure, avoid unnecessarily disconnecting the optical fiber patch cable. In addition, it is
advisable to check the fiber before making other adjustments to the optical system, such as changing the focus
or optical path length. Be sure to check the patch cord for a loose connection, and make sure that the fiber is
kept as straight as possible.
All lasers, especially lasers with resonator cavities that are defined by mechanical tolerances, are delicate
precision instruments and must be handled accordingly. The SS-OCT system is designed to withstand normal
transportation and operating conditions. Do not move the system while it is connected and in operation.

SS-OCT Base Unit Chapter 1: Introduction
Page 4 MTN013142-D02
Optical Cleaning
Good performance and image quality of the OCT imaging system relies on cleanoptical connections.Whenever
using the Thorlabs OCT system, the following guidelines for optical fiber connection should be followed:
1) Always make sure that the light source is switched off when you clean the fiber.
2) Always inspect and clean the fiber end before plugging it into a receptacle.
3) Always cover the fiber end that is not in use with a fiber cap or dust protection cover.
Use a fiber inspection scope to verify if the fiber cleaning process was successful.
Figure 1 Thorlabs Fiber Inspection Scope FS201
Fiber Cleaning Using the FBC250
Fiber bulkheads and connectors can be cleaned using the FBC250 2.5 mm Fiber Bulkhead and Connector
Cleaner. This fiber cleaner features an extended mode, which is useful for panels with multiple bulkhead
connectors or other tight spaces. For detailed cleaning procedures, please see the FBC250 manual on the
Thorlabs website.
Figure 2 FBC250 Extended Mode
Service
Only trained and approved Thorlabs personnel are qualified to service the system. Please contact Thorlabs’
OCT support (see Chapter 12) for more information.
Accessories and Customization
The OCT base unit can easily be adapted for custom interfaces. To achieve the listed specifications however
this system should only be used with the accessories that Thorlabs provides. Any modification or maintenance
by unqualified personnel will render the warranty null and void, leaving Thorlabs free of liability. Please contact
Thorlabs’ OCT support (see Chapter 12) for questions on customization.

SS-OCT Base Unit Chapter 2: Setup
Rev C, December 17, 2021 Page 5
Chapter 2 Setup
2.1. Unpacking
Carefully unpack the components from the transport boxes. Makesure that all components have been delivered
according to the packing list included in the transport box. After unpacking, store the packing cartons and
inserts. You may need them in case of a service or upgrade of your OCT system.
2.2. System Connections
Base Unit Connections
All OCT base unit connections are located on the back of the device.
Figure 3 Connections on the Back Plane of the OCT Base Unit
A. Mains switch
B. SMA connector for OCT signal to connect to AlazarTech ATS9351 or ATS9360
C. SMA connector for DAQ k-clock to connect to AlazarTech ATS9351 or ATS9360
D. USB data port for connection to PC (USB 2.0 Type B Interface)
E. Probe fiber connector (FC/APC)
F. Interlock (2.5mm Audio Jack)
G. Scanner connection port (LEMO, 19 Pin)
H. VHDCI Data Port to connect to the NI PCIe-6351
I. Handheld Scanner or Auxiliary Connection Port (LEMO, 14 Pin; only in Vega™units)
J. SMA Connector for CWL Trigger to connect to AlazarTech ATS9351 or ATS9360
a. Note: This port remains unused in a default configuration.
K. SMA Connector for DAQ Trigger to connect to AlazarTech ATS9351 or ATS9360
L. SMA Connector for SYNC Trigger to connect to AlazarTech ATS9351 or ATS9360
M. Power Plug and Fuse Storage
M
B
C
D
E
F
G
I
A
J
K
L
H

SS-OCT Base Unit Chapter 2: Setup
Page 6 MTN013142-D02
Internal Electrical Connections
The USB connection to the PC is used for the control communication between the software and the base unit.
Acquisition and shaping of the spectral information is performed using the SYNC trigger, DAQ trigger and k-
clock SMA connections; the VHDCI data connection performs device control tasks.
Electrical Interfaces to Imaging Scanner
For connecting to a scanner application, two different interfaces are available.
•The Galvo Scanner connection port is intended for use with dedicated Thorlabs imaging scanners
OCTG and OCTP.
•The OCTH Scanner connection port is intended for use with dedicated Thorlabs imaging scanner
OCTH and furthermore allows the use of a custom scanner. It hosts two analog signals for driving
separate actuators (e.g. Galvanometer scanners), as well as communication lines and supply
voltages. The OCTH Scanner is currently available only for Vega™.
Imaging Scanner –Electrical Interfaces
Galvo Scanner
Lemo ECG.2B.319.CLL
OCTH Scanner (Only Available on Vega™Base Units)
Lemo ECA.1B.314.CLL
Table 1 Electrical Interfaces
Please contact Thorlabs’OCT support (see Chapter 12) for information regarding the pin configuration.
2.3. Optical Interface to Imaging Scanner
The base unit incorporates one FC/APC fiber interface depending on the internal fiber architecture. Table 2
lists the single mode fiber types used with the different base units. Fiber types in customized systems may
differ.
Imaging Scanner - Optical Interface
Base Unit Series
Fiber Plug / Receptacle
Single Mode Fiber
Vega™
FC/APC
Corning SMF28e+
Atria™
FC/APC
Corning HI1060
Table 2 Optical Interface