Callisto 930 nm OCT Imaging System

Let Thorlabs Help with Your Imaging Project!

We recognize that our customers have unique application requirements. For this reason, we stand ready to discuss how our OCT systems can be adapted to meet your needs. You can easily contact us directly at oct@thorlabs.com or via our online request form; an OCT representative will contact you shortly. We are happy to assist with purchasing or information requests:

• Request a Quote: E-mail us with a list of parts or specifications you want.
• Technical Consultation: Ask our engineers for help with configuring a system.
• Sample Testing: Send us your sample and let our engineers determine the right OCT configuration for you.
• Request a Demo: Demos are available for customers in the US and Europe through our Newton, NJ and Lübeck, Germany locations.
• OEM and Custom Projects: Click here to learn about our OEM capabilities.

Features

• Configurable OCT Systems Optimized for High-Sensitivity Imaging
  • 1.2 kHz A-Scan Rate and 107 dB Sensitivity
  • 7 µm Axial Resolution in Air with 1.7 mm Imaging Depth (930 nm Center Wavelength)
• Includes Computer and ThorImage OCT Software Package (See the Software Tab)
• Build-Your-Own and Preconfigured Systems Available
• See the Brochures Tab for More Information on Thorlabs' OCT Systems

Choose Components to Build or Customize Your OCT System

• One 930 nm, High-Sensitivity Base Unit (Required)
• Standard, User-Customizable, and Handheld Scanners Available
• Scan Lens Kits to Optimize Lateral Resolution and Focal Length for Your Application 
• Ring- and Immersion-Style Sample Z-Spacers for Air or Liquid Imaging Applications
• Scanner Stand and Translation Stage Accessories
• Contact Our OCT Team to Request a Quote and Discuss Building a System 

Optical Coherence Tomography (OCT) is a noninvasive optical imaging technique that produces real-time, 2D cross-sectional and 3D volumetric images of a sample. This technique provides structural information about the sample based on light backscattered from different layers of material within that sample, producing images with micron-level resolution and millimeters of imaging depth. OCT imaging can be considered as an optical analog to ultrasound imaging that achieves higher resolution at the cost of decreased penetration depth. In addition to high resolution, the non-contact, noninvasive nature of OCT makes it well suited for imaging samples such as biological tissue, small animals, and industrial materials.  

Thorlabs' Callisto Series of OCT Imaging Systems are designed for high sensitivity and are ideal for imaging static, in vitro samples. The 64-bit software pre-installed on the included computer displays and processes 2D and 3D OCT data in real time. Choose from a number of scanner options including a robust standard scanner, user-customizable scanner, and the portable handheld scanner. Optional accessories are available below to customize your OCT system to meet the requirements of your application. Additionally, Thorlabs offers a complete, preconfigured OCT system for 930 nm based on the components sold on this page.

The components below can also be used to upgrade your existing Thorlabs OCT system with additional features and are fully compatible out of the box with Thorlabs' OCT systems and accessories. While most systems are upgradable, we recommend contacting the OCT Team to determine the optimal solution for your system and intended application.

Click on the Image Below or in the Table to the Right for Details on Customization Options

ThorImage OCT Software Index

• Introduction
• Imaging Modes
  • 2D Mode for Cross-sectional Imaging
  • 3D Mode for Volume Imaging
  • Doppler Mode for Doppler Flow Imaging
  • Speckle Variance Mode for Angiographic Imaging
• Externally-Triggered Acquisition for Synchronized Measurements
• Easy Probe Calibration for Different Configurations
• Video Showing Screencast of Rendering Capabilities

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The ThorImage OCT Window in Volume Rendering Mode

ThorImage OCT Software

• Interactive Scan Position Control through Video Display (Draw and Scan)
• Advanced Dataset Management
• High-Speed Volume Rendering of 3D Data
• Doppler and Speckle Variance Imaging
• Versatile Scan and Acquisition Control

ThorImage OCT is high-performance data acquisition software that is included with all Thorlabs Spectral Domain OCT systems. This 64-bit Windows-based software package is capable of data acquisition, processing, scan control, and displaying OCT images. Additionally, NI LabVIEW and C-based Software Development Kits (SDKs) are available, which contain a complete set of libraries for measurement control, data acquisition and processing, as well as storage and display of OCT images. The SDKs provide the means for developing highly specialized OCT imaging software for every individual application.

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Various acquisition parameters can be adjusted in ThorImage OCT.

Scan Control

ThorImage OCT provides numerous scan and acquisition controls. The camera integrated in the probe of our OCT system provides live video images in the application software. Defining the scan line for 2D imaging or the scan area for 3D imaging is accomplished through the easy-to-use "Draw and Scan" feature by clicking on the video image. The scan pattern can also be adjusted by specifying parameters in the controls of the software. Additionally, one can further set processing parameters, averaging parameters, and the speed and sensitivity of the device using device presets. By using a high-speed preset, video-like frame rates in 2D and fast volume rendering in 3D are possible, whereas high-sensitivity acquisition is enabled by choosing a preset with a lower acquisition speed.

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The Sample Monitor can be used to define the scan pattern using the "Draw and Scan" feature.

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The Dataset Management Window of ThorImage OCT

Dataset Management

ThorImage OCT provides advanced dataset management capabilities, which allow opening several datasets simultaneously. Datasets are uniquely defined using an identifier consisting of study (or test series) name and an experiment number. Grouping of datasets is possible using the same study name. The "Captured Datasets" list shows an overview of all open datasets, including the study name, the acquisition mode, and preview pictures of the still video image and the OCT data.

Datasets can be exported in various image formats, such as PNG, BMP, JPEG, PDF, or TIFF. Formats suited for post-processing purposes, such as RAW/SRM, FITS, VTK, VFF, and 32-bit floating-point TIFF, are also supported.

The OCT file format native to ThorImage OCT allows OCT data, sample monitor data, and all relevant metadata to be stored in a single file. ThorImage OCT can also be installed and run on computers without an OCT system installed in order to view data.

Third Party Applications

If ImageJ is installed on the computer with ThorImage OCT installed, opening acquired OCT data in ImageJ is one mouse click away, as shown in the image below. This enables a flawless workflow when requiring the advanced image processing functionality provided by ImageJ. Clicking the Explorer button shown below will open the folder and select the file in Windows Explorer where the currently active dataset is stored.

Export buttons are accessible in the Action Toolbar of ThorImage OCT.

Imaging Modes

Different OCT imaging modes can be selected using the mode selector. If the ThorImage OCT software finds a compatible system connected and switched on, all operational modes will be selectable. If no OCT device is present, only the data viewing mode for viewing and exporting OCT data will be available.

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The ThorImage OCT Window in 2D Mode

2D Mode

In the 2D imaging mode the probe beam scans in one direction, thus acquiring cross-sectional OCT images, which are then displayed in real time. Line averaging before or after the Fast Fourier Transform (FFT) is available as well as B-Scan averaging. Image display parameters, such as color mapping, can be controlled in this mode. We have also implemented an option for automatic calculation of the optimum contrast and brightness of the displayed OCT images.

3D Mode

In the 3D imaging mode, the OCT probe beam scans sequentially across the sample to collect a series of 2D cross-sectional images, which are then processed to build a 3D image.

In the ThorImage OCT software, 3D volume datasets can be viewed as orthogonal cross-sectional planes (see below) and volume renderings.

The Sectional View features cross-sectional images in all three orthogonal planes, independent of the orientation in which the data was acquired. The view can be rotated as well as zoomed in and out.

The Rendering View provides a volumetric rendering of the acquired volume dataset. This view enables quick 3D visualization of the sample being imaged. Planes of any orientation can be clipped to expose structures within the volume. The 3D image can be zoomed in and out as well as rotated. Furthermore, the coloring and dynamic range settings can be adjusted.

Utilizing the full potential of our high-performance software in combination with our high-speed OCT systems, we have included a Fast Volume Rendering mode in ThorImage OCT, which serves as a preview for high-resolution 3D acquisitions. In this mode, high-speed volume renderings can be displayed in real-time, providing rapid visualization of samples in three dimensions.

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Rendering View

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Sectional View

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Doppler dataset showing the velocity of a rotated plastic stick.

Doppler Mode

Doppler OCT imaging comes standard with all OCT systems. In the Doppler mode, phase shifts between adjacent A-scans are averaged to calculate the Doppler frequency shift induced by particle motion or flow. The number of lateral axial pixels can be modified to change velocity sensitivity and resolution during phase shift calculation. The Doppler images are displayed in the main window with a color map indicating forward- or backward-directed flow, relative to the OCT beam.

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Speckle variance measurement showing blood vessels of a hand.

Speckle Variance Mode

The speckle variance acquisition mode uses the variance of speckle noise to calculate angiographic images. It can be used to visualize three dimensional vessel trees without requiring significant blood flow and without requiring a specific acquisition speed window. The speckle variance data can be overlaid on top of intensity pictures providing morphological information. Different color maps can be used to display the multimodal pictures.

Externally-Triggered Acquisition

ThorImage OCT and the SDK APIs provide the ability to externally trigger the acquisition of A-Scans. This enables the user to synchronize measurements from different modalities (e.g. vibrometry and synchronized positioning) with an OCT measurement. Synchronization is greatly simplified with all current CameraLink-based Thorlabs OCT systems (a TTL level trigger signal source required). External triggering is available for all imaging modes and can be toggled in the settings dialog in ThorImage OCT.

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Probe Calibration Window in ThorImage OCT

Easy Probe Calibration

Changing to a different scan lens kit (sold below) will generally require a different probe configuration in order to adapt to changes in the optical parameters of the system. When an additional scan lens is purchased for your Thorlabs OCT scanner system, ThorImage OCT enables you to easily create a fitting configuration for your new scan lens by using the calibration sample shipped with the lens and an intuitive step-by-step calibration process (shown in the image to the right).

Video Showing Screencast of ThorImage OCT Rendering Capabilities

In this video, OCT images of a finger are acquired and manipulated in the 3D volume and cross section modes.

Optical Coherence Tomography Tutorial

Optical Coherence Tomography (OCT) is a noninvasive optical imaging modality that provides real-time, 1D depth, 2D cross-sectional, and 3D volumetric images with micron-level resolution and millimeters of imaging depth. OCT images consist of structural information from a sample based on light backscattered from different layers of material within the sample. It can provide real-time imaging and is capable of being enhanced using birefringence contrast or functional blood flow imaging with optional extensions to the technology.

Thorlabs has designed a broad range of OCT imaging systems that cover several wavelengths, imaging resolutions, and speeds, while having a compact footprint for easy portability. Also, to increase our ability to provide OCT imaging systems that meet each customer’s unique requirements, we have designed a highly modular technology that can be optimized for varying applications.

Application Examples

Art Conservation

Drug Coatings

3D Profiling

In-vivo

Small Animal

Biology

Tissue Birefringence

Mouse Lung

Retina Cone Cells

OCT is the optical analog of ultrasound, with the tradeoff being lower imaging depth for significantly higher resolution (see Figure 1). With up to 15 mm imaging range and better than 5 micrometers in axial resolution, OCT fills a niche between ultrasound and confocal microscopy.

In addition to high resolution and greater imaging depth, the non-contact, noninvasive advantage of OCT makes it well suited for imaging samples such as biological tissue, small animals, and materials. Recent advances in OCT have led to a new class of technologies called Fourier Domain OCT, which has enabled high-speed imaging at rates greater than 700,000 lines per second.¹ 

Fourier Domain Optical Coherence Tomography (FD-OCT) is based on low-coherence interferometry, which utilizes the coherent properties of a light source to measure optical path length delays in a sample. In OCT, to obtain cross-sectional images with micron-level resolution, and interferometer is set up to measure optical path length differences between light reflected from the sample and reference arms.

There are two types of FD-OCT systems, each characterized by its light source and detection schemes: Spectral Domain OCT (SD-OCT) and Swept Source OCT (SS-OCT). In both types of systems, light is divided into sample and reference arms of an interferometer setup, as illustrated in Fig 2. SS-OCT uses coherent and narrowband light, whereas SD-OCT systems utilize broadband, low-coherence light sources. Back scattered light, attributed to variations in the index of refraction within a sample, is recoupled into the sample arm fiber and then combined with the light that has traveled a fixed optical path length along the reference arm. A resulting interferogram is measured through the detection arm of the interferometer.

The frequency of the interferogram measured by the sensor is related to depth locations of the reflectors in the sample. As a result, a depth reflectivity profile (A-scan) is produced by taking a Fourier transform of the detected interferogram. 2D cross-sectional images (B-scans) are produced by scanning the OCT sample beam across the sample. As the sample arm beam is scanned across the sample, a series of A-scans are collected to create the 2D image.

Similarly, when the OCT beam is scanned in a second direction, a series of 2D images are collected to produce a 3D volume data set. With FD-OCT, 2D images are collected on a time scale of milliseconds, and 3D images can be collected at rates now below 1 second. 

Spectral Domain OCT vs. Swept Source OCT

Spectral Domain and Swept Source OCT systems are based on the same fundamental principle but incorporate different technical approaches for producing the OCT interferogram. SD-OCT systems have no moving parts and therefore have high mechanical stability and low phase noise. Availability of a broad range of line cameras has also enabled development of SD-OCT systems with varying imaging speeds and sensitivities.

SS-OCT systems utilize a frequency swept light source and photodetector to rapidly generate the same type of interferogram. Due to the rapid sweeping of the swept laser source, high peak powers at each discrete wavelength can be used to illuminate the sample to provide greater sensitivity with little risk of optical damage.

FD-OCT Signal Processing

In Fourier Domain OCT, the interferogram is detected as a function of optical frequency. With a fixed optical delay in the reference arm, light reflected from different sample depths produces interference patterns with the different frequency components. A Fourier transform is used to resolve different depth reflections, thereby generating a depth profile of the sample (A-scan).

¹V.Jayaraman, J. Jiang, H.Li, P. Heim, G. Cole, B. Potsaid, J. Fujimoto, and A. Cable, "OCT Imaging up to 760 kHz Axial Scan Rate Using Single-Mode 1310 nm MEMs-Tunable VCSELs with 100 nm Tuning Range," CLEO 2011 - Laser Applications to Photonic Applications, paper PDPB2 (2011).

Brochure and Configuration Chart

The buttons below link to PDFs of printable materials and a graphical customization guide for our Callisto Series OCT Systems.

Thorlabs offers a variety of OCT Imaging Systems to meet a range of application requirements. The OCT base unit and scan lens kit are key to OCT system performance. Significant performance characteristics, including axial resolution, A-Scan rate, and imaging depth, are entirely or strongly dependent on the design of the OCT base unit. The choice of scan lens kit determines other parameters, such as lateral resolution and field of view. Thorlabs offers a variety of OCT base units and scan lens kits that provide foundations for systems with a wide range of capabilities. The tables below present key performance parameters of our base units and include links to our other OCT imaging system pages. We encourage you to contact us directly at oct@thorlabs.com or via our online request form to discuss specific imaging requirements.

900 nm OCT Base Units

• These Item #s are OCT base units that can be customized using a wide selection of OCT scanners, lens kits, and optional accessories.
• Axial resolution and actual imaging depth are dependent on the optical properties of the sample being imaged.
• Values for the Callisto and Ganymede systems are typical and were measured using a scanner with a common reference/sample path and 50% path split. 

1300 nm OCT Base Units

• These Item #s are OCT base units that can be customized using a wide selection of OCT scanners, lens kits, and optional accessories.
• Axial resolution and actual imaging depth are dependent on the optical properties of the sample being imaged.
• Values for the Telesto systems are typical and were measured using a scanner with a common reference/sample path and 50% path split. The value measured for the Vega system is typical and was measured using a scanner with a dual path setup.