Single Image Structured Illumination using Hilbert Transform Demodulation

Description:

INV-17043

Background

Various optical sectioning techniques have provided pathologists and clinicians with some ability to image biological samples non-invasively at or below a surface such as skin. The currently used structured illumination microscopy (SIM) method has advantages over confocal microscopy as it achieves sectioning at depth by removing undesired light from out-of-focus planes within a specimen. However, it generally requires at least three modulated images with discrete phase shifts of 0, 120, and 240 deg to produce sectioning, making in vivo imaging difficult. Hence, there is a need for a single imaging technique.

 

Technology Overview

Researchers at Northeastern University have designed an optical device using Hilbert transform demodulation to produce both sectioning and depth information relative to a reference plane (e.g. coverslip) using only a single image. This device produces a high-quality sectioned image containing both axial and lateral information of an object. 

The process of imaging consists of:

• Taking a single modulated image of the sample
• Estimation and subtraction of out-of-focus light from the original image
• Reservation of modulated sectioned image
• Demodulation of the image

 

Benefits

• The device reduces:
  • Image acquisition time to 1/3rd of the previously required time
  • Noise and stray light
  • Complexity and cost of image processing
• Increases robustness in turbid media as the imaging is not phase-dependent
• Produces better contrast with a single image within turbid media than the traditional 3-image SIM technique

 

Applications

• Biological imaging within turbid media (subdermal) such as-
  • Skin cancer diagnosis, tumor margin examination
  • In vivo imaging
  • Biomedical imaging for better diagnosis e.g. in ophthalmology 
• Quality control of manufactured products by topological imaging

 

Opportunity

• License
• Partnering
• Research collaboration