Description

The 20D Large Lens is an essential tool in the field of ophthalmology, renowned for its precision and versatility. Crafted by leading manufacturers such as Volk, Katena, and Ocular Instruments, this lens is designed for indirect binocular ophthalmoscopy, providing exceptional clarity and detail during retinal examinations.

Key Features

• Biconvex, Aspheric Design: The lens features a biconvex, double aspheric design, offering a dioptric power of +20 diopters. This configuration ensures a clear, real, inverted aerial image, enhancing the practitioner's ability to examine the retina with accuracy.

• Magnification and Field of View: With an image magnification of approximately 3.13x and a field of view ranging from 40° to 60°, the 20D Large Lens strikes a perfect balance between magnification and panoramic vision. This makes it ideal for viewing the macula, optic nerve, and retinal lesions.

• Working Distance: A working distance of 47–50 mm from the cornea allows for comfortable use, particularly beneficial in pediatric examinations and scenarios requiring scleral indentation.

Construction and Materials

• High-Quality Optics: Constructed with premium glass optics, the lens often includes anti-reflective coatings to minimize glare. Available in a variety of colors, it caters to both aesthetic preferences and functional needs.

• Durability: Weighing approximately 56g, the lens is robust yet lightweight, ensuring ease of handling during prolonged use.

Use Cases

The 20D Large Lens is widely recognized as a "workhorse" in clinical settings, suitable for:

• General retinal examinations
• Pediatric and challenging patient scenarios
• Use in operating rooms and neonatal intensive care units (NICU)

Care and Maintenance

To maintain optimal performance, the lens should be cleaned with mild, pH-neutral detergents and rinsed with sterile water. Disinfection is recommended using high-level disinfectants, especially if the lens contacts the eye. For surgical use, sterilization methods such as Ethylene Oxide or Steam Sterilization are advised.

Additional Features

• Reusable and Single-Use Options: Available in both reusable and single-use sterile versions, some models offer anti-reflective coatings and optional engravings.

• Color Durability: Colored rings may fade with repeated sterilization, though this is purely cosmetic.

The 20D Large Lens remains a vital instrument for ophthalmologists, providing unparalleled insight into the intricate structures of the eye while ensuring patient comfort and safety through its non-contact design.