Description

The 20D Large Lens is an essential tool for ophthalmic professionals, designed specifically for indirect ophthalmoscopy. This handheld, biconvex, aspheric lens is crafted to provide exceptional performance during retinal examinations when used with a binocular indirect ophthalmoscope (BIO).

Key Features

• Dioptric Power: +20 diopters, offering a balanced compromise between magnification and field of view.
• Optical Design: Double aspheric glass optics with anti-reflective coatings, ensuring clear and precise imaging.
• Field of View: Ranges from 46° to 60°, depending on the manufacturer, suitable for comprehensive retinal evaluation.
• Image Magnification: Approximately 3.0x to 3.25x, providing detailed visualization of the retina.
• Working Distance: 47–50 mm from the cornea, facilitating comfortable use.

Versatility and Use

This lens is widely regarded as the standard for general retinal evaluation, suitable for both adult and pediatric patients. It excels in situations where slit lamp examination is not feasible, such as with patients who have nystagmus or require scleral indentation. The 20D Large Lens allows for effective examination of the fundus, macula, and optic nerve, reaching up to the mid-peripheral retina.

Design and Ergonomics

Weighing approximately 56g, the lens is designed for ease of manipulation and ergonomic comfort. It is available in various ring colors, including black, blue, gold, and more, allowing for personalization. The lens is offered in both autoclavable and single-use designs, compatible with multiple sterilization methods, enhancing its practicality and reducing cross-contamination risks.

Maintenance Guidelines

To maintain optimal performance, the lens should be cleaned with a mild, pH-neutral detergent and rinsed with sterile water. High-level disinfectants are recommended for disinfection, while alcohol wipes and microfiber cloths should be avoided. Proper storage in a clean, dry environment is essential after cleaning.

Additional Benefits

The 20D Large Lens is available from multiple reputable manufacturers, such as Volk and Ocular Instruments, often featuring options like anti-reflective coatings and custom engravings. Its widespread use and recognition in the field underscore its reliability and effectiveness, making it a valuable asset for routine and advanced retinal diagnostics.