Correction of chromatic aberrations in GRIN endoscopes

Area of Science:

• Optics
• Medical Imaging
• Materials Science

Background:

• Gradient-index (GRIN) lenses are used in endoscopes, replacing traditional objective and relay lenses.
• Existing GRIN lenses suffer from significant chromatic aberrations, impacting image quality.
• Axial color originates from the relay lens, and lateral color from the objective lens.

Purpose of the Study:

• To develop a method for correcting both axial and lateral chromatic aberrations in GRIN endoscopes.
• To improve the optical performance and image fidelity of GRIN endoscope systems.
• To investigate the simultaneous correction of monochromatic aberrations.

Main Methods:

• A negative lens was cemented to a shortened GRIN relay lens.
• This combined optical element was designed to counteract chromatic aberrations.
• The system's performance was evaluated, considering mechanical centration requirements.

Main Results:

• The proposed negative lens and GRIN relay lens combination effectively corrects both axial and lateral chromatic aberrations.
• Commercially available optical components were utilized for the correction system.
• The developed correction method imposes less stringent mechanical centration tolerances compared to ocular-integrated correctors.

Conclusions:

• A practical and effective method for chromatic aberration correction in GRIN endoscopes has been demonstrated.
• This approach enhances the usability and performance of GRIN endoscope technology.
• Further consideration was given to the impact on monochromatic aberrations.