Description

The 20D Large Lens is an essential tool for ophthalmologists, designed specifically for binocular indirect ophthalmoscopy (BIO). Renowned for its effectiveness in retinal examinations, this lens is widely recognized and often associated with leading manufacturers like Volk.

Key Features

• Optical Design: The lens features a double aspheric, biconvex design, providing exceptional optical performance. With a dioptric power of +20 diopters, it offers a comprehensive field of view, crucial for detailed retinal assessments.

• Field of View and Magnification: The lens provides a field of view ranging between 46° and 60°, with an image magnification of approximately 3.13x. This balance allows for effective examination of the mid-peripheral retina and optic disc size estimation.

• Working Distance: A working distance of around 50 mm from the cornea ensures comfortable and precise operation during examinations.

Material and Build

• Construction: Crafted with aspheric glass optics and housed in colored aluminum components, the lens is available in various colors including Black, Blue, Gold, and more. This variety allows for personalization and easy identification.

• Design Variants: The lens comes in standard, autoclave sterilizable (ACS®), and single-use designs, catering to different clinical needs and preferences.

Cleaning and Sterilization

• Guidelines: Recommended cleaning involves manual methods using alcohol wipes, with disinfection options including glutaraldehyde and bleach solutions. The lens is compatible with certain sterilization systems like ethylene oxide gas but not with steam autoclave.

• Maintenance: Proper drying and storage are essential, along with regular inspection to ensure the lens remains undamaged and ready for use.

Additional Features

• Customization: Engraving options are available for both the lens and its case, with potential for custom color choices, enhancing the professional utility of the lens.

• Certifications: The lens typically holds certifications such as CE, FDA, and ISO13485, though these may vary by manufacturer.

Usage Notes

The 20D Large Lens is highly regarded among BIO condensing lenses for its balance of field of view, stereopsis, and magnification. While not typically used for slit lamp examinations, it remains a cornerstone in comprehensive fundus assessment, providing reliable performance for eye care professionals.