Multi-megahertz OCT: High quality 3D imaging at 20 million A-scans and 4.5 GVoxels per second.
We present ultra high speed optical coherence tomography (OCT) with multi-megahertz line rates and investigate the achievable image quality. The presented system is a swept source OCT setup using a Fourier domain mode locked (FDML) laser. Three different FDML-based swept laser sources with sweep rates of 1, 2.6 and 5.2MHz are compared. Imaging with 4 spots in parallel quadruples the effective speed, enabling depth scan rates as high as 20.8 million lines per second. Each setup provides at least 98dB sensitivity and approximately 10microm resolution in tissue. High quality 2D and 3D imaging of biological samples is demonstrated at full scan speed. A discussion about how to best specify OCT imaging speed is included. The connection between voxel rate, line rate, frame rate and hardware performance of the OCT setup such as sample rate, analog bandwidth, coherence length, acquisition dead-time and scanner duty cycle is provided. Finally, suitable averaging protocols to further increase image quality are discussed.
Wieser
Wolfgang
W
Lehrstuhl für BioMolekulare Optik, Fakultät für Physik, Ludwig-Maximilians-Universität München,Oettingenstr. 67, 80538 Munich, Germany.
Biedermann
Benjamin R
BR
Klein
Thomas
T
Eigenwillig
Christoph M
CM
Huber
Robert
R
D018553:Cucumis sativus / Q000033:anatomy & histology; D005385:Fingers / Q000033:anatomy & histology; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods* / Q000592:standards*; D007368:Interferometry; D007834:Lasers; D041623:Tomography, Optical Coherence / Q000295:instrumentation* / Q000379:methods*