A line-field swept-source optical coherence tomography (OCT) system features a cat's-eye tunable laser that is free-space coupled to an interferometer. The laser employs a single angled facet (SAF) edge-emitting gain chip producing a beam with multiple spatial modes. By preserving these higher-order modes through free-space couplingavoiding single-mode fiberthe system generates a line with a more uniform, top-hat intensity profile when projected onto a sample, such as a patient's retina. This profile mitigates the Gaussian power roll-off typically associated with single spatial mode beams, ensuring adequate signal-to-noise ratio across the line while adhering to optical safety limits. The laser cavity includes a thin-film interference bandpass filter mounted on an angle control actuator, allowing for wavelength sweeping by tilt-tuning the filter. The system integrates a line-scan sensor and is designed for manufacturability, offering improved imaging quality for ophthalmic diagnostics and other applications requiring high-resolution, cross-sectional imaging.

A line-field optical coherence tomography (OCT) system and method provide enhanced imaging accuracy through k-linearization of interference data. The system includes a swept laser source, a line-field sensor, and a single board computer (SBC) with processing capabilities. The system uses a frequency reference to produce a periodic reference pattern, which is detected by a subset of pixels in the line-field sensor. The SBC determines a resampling curve based on the reference pattern to correct non-linearities in the wavelength tuning of the laser. The resampling curve is applied to k-linearize the interference data, enabling the generation of high resolution transform-limited depth profiles through inverse Fourier transform. Methods are disclosed for recalculating the resampling curve periodically, continuously, or adaptively based on a linearity threshold. The system can further update the laser's tuning function dynamically to ensure consistent performance. These advancements enable precise and efficient OCT imaging for applications such as ophthalmology, angiography, and other diagnostic uses.