Types of Rigid Borescope Lenses

Types of Rigid Borescope Lenses

June 18, 2021

Since their creation in the 1960s, borescopes have found homes in a wide variety of industrial applications. The original version, which features a straight barrel rather than a flexible cord, still has many useful applications. How to best use them depends on the types of rigid borescope lenses being used. Ultimately, the lenses chosen will significantly impact the nature of images captured by the borescope.

The Basics of Rod Lenses

The standard types of rigid borescope lenses commonly equipped to a device are best known by their original creator’s name. Harold Horace Hopkins was a physicist who passed away relatively recently in 1994 at the age of 76.

His best-known contributions are a variety of optical equipment, including zoom lenses and rod-lens endoscopes that people still commonly use today. Gradient Lens carries both Hopkins’ type and our own endoGRINS design. Our design is a more cost-effective and streamlined reimaging of the original, ingenious design.

Uses for Achromatic Lenses

Standard lenses are subject to the illusions of light passing through glass. Achromatic lenses cut back the occurrences of chromatic aberrations. The result is a sharper and more reliable image produced by the rigid borescope. The design utilizes a convex glass lens affixed to a concave glass lens, resulting in a tighter transmission of light wavelengths. The difference is obvious at a glance, as uncorrected images from a standard lens result in blurring as color are perceived in distorted layers.

Gradient Index Rod Lenses

Gradient-index, or GRIN, refers to the concave effect of lenses commonly found in nature. This borescope lens mimics how our own eyes see and are affected by light. The result is a quality image in both short and long-range situations. The design also reduces chromatic and other types of light-wave originations distortions. On a borescope, the result is an easy to manage perspective that doesn’t require jostled settings to bring an image into sharp focus.