Terahertz single pixel imaging with an optically controlled dynamic spatial light modulator.

Area of Science:

• Optics and Photonics
• Semiconductor Physics
• Terahertz (THz) Imaging

Background:

• Terahertz (THz) imaging offers unique capabilities for non-destructive analysis due to its ability to penetrate various materials.
• Developing dynamic and high-resolution THz spatial light modulators (SLMs) is crucial for advancing real-time THz imaging applications.

Purpose of the Study:

• To introduce a novel single-pixel terahertz (THz) imaging technique.
• To demonstrate the use of an optically controlled semiconductor spatial light modulator (SLM) for dynamic THz mask generation.

Main Methods:

• Utilized optical photoexcitation of a high-resistivity silicon wafer to modulate THz transmission in real-time.
• Employed a digital micro-mirror device (DMD) to encode spatial patterns onto the optical beam, creating dynamic THz masks.
• Acquired THz images using a single-pixel detector with masks of varying complexity (63 to 1023 pixels).

Main Results:

• Achieved real-time modulation of THz transmission by optically controlling semiconductor electromagnetic properties.
• Successfully generated and applied complex THz masks using a digital micro-mirror device (DMD).
• Demonstrated THz image acquisition speeds of up to 1/2 Hz with high fidelity.

Conclusions:

• The presented optically controlled SLM technique is a viable method for real-time THz imaging.
• This approach enables dynamic mask generation for high-fidelity terahertz imaging with a single-pixel detector.
• The findings pave the way for advanced applications in THz microscopy and sensing.