Multicolor structured illumination microscopy and quantitative control of polychromatic light with a digital...

Area of Science:

• Optical Microscopy
• Super-Resolution Imaging
• Biophysics

Background:

• Linear structured illumination microscopy (SIM) offers super-resolution without stringent photophysical sample requirements.
• Current multicolor SIM systems primarily use liquid crystal on silicon (LCoS) spatial light modulators (SLMs).
• Digital micromirror devices (DMDs) are cost-effective and faster alternatives but are limited to single-wavelength SIM due to the blazed grating effect.

Purpose of the Study:

• To develop quantitative tools for overcoming the blazed grating effect in DMD-based multicolor SIM.
• To enable the use of DMDs in polychromatic structured illumination microscopy applications.
• To construct and validate a three-color DMD microscope for biological imaging.

Main Methods:

• Developed a closed-form solution for blaze and diffraction conditions specific to DMDs.
• Created forward models for DMD diffraction, pattern projection, and aberrations.
• Constructed a three-color DMD microscope and implemented a high-resolution optical transfer function measurement technique.

Main Results:

• Successfully demonstrated multicolor structured illumination microscopy using a DMD.
• Quantified the impact of DMD aberrations on image quality.
• Achieved super-resolution imaging in fixed and live biological samples with the developed system.

Conclusions:

• The developed quantitative tools and models enable efficient polychromatic light patterning with DMDs.
• This work extends the application of DMDs to multicolor SIM, previously limited to LCoS SLMs.
• The three-color DMD microscope provides a powerful, cost-effective platform for advanced biological imaging.