A swept-source laser, also known as a wavelength-swept laser, is a type of laser that rapidly and continuously changes its emission wavelength over time. This continuous wavelength tuning is achieved by either mechanically or electronically sweeping the laser frequency across a broad range. Swept-source lasers are commonly used in various applications, especially in the field of optical coherence tomography (OCT).
Key characteristics of swept-source lasers include:
Wavelength tuning: The primary feature of a swept-source laser is its ability to tune or sweep its emitted wavelength rapidly and continuously. This tuning can be achieved through various methods, such as changing the cavity length or using tunable components within the laser.
Broad wavelength range: Swept-source lasers often cover a broad wavelength range, enabling them to be used for imaging or sensing in different regions of the electromagnetic spectrum.
High sweep rates: These lasers can have high sweep rates, allowing for the rapid acquisition of data. In the context of OCT, high sweep rates are particularly advantageous for obtaining high-resolution images of biological tissues.
Applications in OCT: Swept-source lasers are widely used in optical coherence tomography, a non-invasive imaging technique that provides detailed cross-sectional images of biological tissues. OCT is employed in ophthalmology, cardiology, dermatology, and other medical fields for diagnostics and imaging.
Range and velocity measurement: The ability to rapidly sweep the laser wavelength is also valuable for applications such as range finding and velocity measurements, as the time delay between the emitted signal and the received signal can be used to determine distances or velocities.
Swept-source lasers have contributed significantly to advancements in medical imaging and diagnostic technologies. They offer advantages in terms of speed, sensitivity, and resolution, making them a preferred choice in certain applications where high-performance imaging and precise measurements are essential.