Related Experiment Video
Updated: Mar 25, 2026
10:01
Demonstration of a Hyperlens-integrated Microscope and Super-resolution Imaging
Published on: September 8, 2017
8.3K
Effect of pinhole shape on projection resolution
L C Johnson1, S C Moore, S D Metzler
1Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA.
Physics in Medicine and Biology
|February 20, 2016
Summary
Rounded corners on square pinholes for pre-clinical SPECT imaging reduce spatial resolution. Perfect square pinholes offer superior performance compared to rounded ones when sensitivity and field-of-view are matched.
Area of Science:
- Medical Imaging
- Nuclear Medicine
- Pre-clinical Research
Background:
- Designing a dual-resolution pre-clinical single-photon emission computed tomography (SPECT) system.
- Focus on small field-of-view (FOV) applications like mouse cardiac imaging.
- Square pinholes offer higher sensitivity than circular pinholes due to efficient detector tiling.
Purpose of the Study:
- Investigate the impact of rounded corners in square pinholes on spatial resolution.
- Compare the performance of square pinholes with rounded corners to ideal square pinholes.
- Evaluate how fabrication imperfections affect SPECT imaging quality.
Main Methods:
- Simulated different pinhole full-acceptance angles and roundedness values.
- Matched non-square pinholes (circular) to square pinholes for sensitivity and FOV.
- Calculated sensitivity including geometric, penetrative, and packing fraction.
- Estimated spatial resolution using full-width at half-maximum (FWHM) and full-width tenth-maximum (FWTM).
Main Results:
- FWHM increased as pinhole shape deviated from square towards circular.
- FWTM showed minimal change across different pinhole shapes.
- Roundedness in square pinholes negatively impacted spatial resolution compared to ideal square pinholes.
Conclusions:
- A perfect square pinhole is more desirable for optimal spatial resolution in SPECT imaging.
- Rounded corners, an unavoidable fabrication artifact, degrade imaging performance.
- Findings are crucial for designing high-resolution pre-clinical SPECT systems.
Related Concept Videos
01:18Imaging Biological Samples with Optical Microscopy
12.2K
Optical microscopy uses optic principles to provide detailed images of samples. Antonie van Leeuwenhoek designed the first compound optical microscope in the 17th century to visualize blood cells, bacteria, and yeast cells. In 1830, Joseph Jackson Lister created an essentially modern light microscope. The 20th century saw the development of microscopes with enhanced magnification and resolution.
In optical microscopy, the specimen to be viewed is placed on a glass slide and clipped on the stage...
In optical microscopy, the specimen to be viewed is placed on a glass slide and clipped on the stage...
12.2K
01:16Focusing of Light in the Eye
7.2K
Light rays enter the eye through the cornea, a transparent dome-shaped tissue that is the eye's outermost layer. The cornea bends or refracts, light rays traveling to the pupil. The shape of the cornea determines how much of the light is bent and whether the image will be focused correctly on the retina at the back of the eye. Once the light has passed through both refraction layers, it converges into a single focal point onto a small area. This is where photoreceptors start transforming...
7.2K
01:16Confocal Fluorescence Microscopy
22.0K
Confocal microscopy is an advanced microscopic technique. The prime advantage of the confocal microscope over other microscopy techniques is its ability to block the out-of-focus light from the illuminated samples using pinholes. It is widely used with fluorescence optics to obtain high-resolution, sharp contrast images. Unlike optical microscopes, confocal microscopes use a focused beam of light laser to scan the entire sample surface at different z-planes. These microscopes are, therefore,...
22.0K
01:37Super-resolution Fluorescence Microscopy
14.8K
Super-resolution fluorescence microscopy (SRFM) provides a better resolution than conventional fluorescence microscopy by reducing the point spread function (PSF). PSF is the light intensity distribution from a point that causes it to appear blurred. Due to PSF, each fluorescing point appears bigger than its actual size, and it is the PSF interference of nearby fluorophores that causes the blurred image. Various approaches to achieving higher resolution through SRFM have recently been...
14.8K