In a new development in the world of science and technology, researchers at the Indian Institute of Science (IISc) have demonstrated that a brain-inspired image sensor can supersede the diffraction limit of light in detecting extremely small entities. These entities could include cellular components or nanoparticles that are normally invisible to contemporary microscopes.
Understanding the Technology
The mentioned technology is an innovative combination of optical microscopy, a neuromorphic camera, and machine learning algorithms. It represents a remarkable advancement in identifying objects less than 50 nanometers in size. Presently, the diffraction limit hampers optical microscopes from differentiating between two objects smaller than a given size, generally around 200-300 nanometers.
The role of the neuromorphic camera here is truly noteworthy. This type of camera emulates how the human retina transforms light into electrical impulses. In such cameras, each pixel functions autonomously, producing sparse and a lesser quantity of data, akin to the working of the human retina. This mechanism allows the camera to sample the environment with a superior temporal resolution, distinguishing it from conventional cameras where each pixel records the light’s intensity falling on it. The pixels are collectively employed to recreate an image of the object.
In their experiment, the researchers utilized the neuromorphic camera to locate individual fluorescent beads tinier than the diffraction limit. This was achieved through the projection of laser pulses of both high and low intensities, along with the measurement of the variance in the fluorescence levels.
The Significance of this Technique
The potential applications of this novel approach are expansive and could strongly influence biology, chemistry, and physics. More specifically, it could aid in comprehending the fundamental principles of biological processes such as self-organization.
During their research, the team successfully tracked the movement of a fluorescent bead moving freely in an aqueous solution by using this technique.
Stochastic Processes: An Overview
A stochastic process, also referred to as a random process, is essentially a process steered by chance. An example of a stochastic process is radioactive decay. In this phenomenon, every atom possesses a constant probability of disintegrating within any given time span.
Exploring the Diffraction Limit
The diffraction limit is an inherent physical restriction on an optical system’s capability to resolve or distinguish between two objects situated close to each other. The minimum resolvable distance between two sources of light depends on the size of the aperture or lens used to observe the objects, in addition to the light’s wavelength.
In real-world applications, this implies that even with an ideal lens or telescope, there is a boundary to how much detail can be identified in an image. If objects are closer together than the diffraction limit, they will appear blurred or indistinguishable in the resultant image.
Source:TH