What Is a Borescope? - Best Endoscopes

Inspection camera, viewing system, optical device, or optical instrument — people turn to a variety of different descriptive terms to explain what a borescope is. At its core, and in plain English, though, a borescope is a camera-connected electrical appliance that allows people to see inside small and tricky spaces.

Borescopes designed for use in the medical field, called endoscopes, have made the rise in innovative keyhole surgeries that allow patients to recover much more quickly possible. Outside of cutting-edge medicine, borescopes also have countless (and often equally important) applications. Different types of borescopes enable professionals across industries to see precisely what they need to, without having to disassemble large structures, potentially risking their safety or the structural integrity of the space in which they are working.

Why and when were borescopes first invented, how are they used, and what types of borescopes are currently found on the market? Read on to learn more about these fascinating and incredibly useful tools.

A Brief History of Borescopes

Early versions of the modern borescope were in use as early as World War II, when they could be used to examine the inside bores of guns. This is where the name “borescope” comes from. A borescope similar to those found on the market today was invented in the 1960s, by physicist Narinder Kapany and optical physicist Brian O’Brien, both from the United States.

This borescope used a rigid tube and an optical visual inspection system, just like some modern borescopes do — but borescopes have come a long way since the 1960s.

Which Industries Use Borescopes?

Borescopes are used in a huge number of different fields, as any industry in which people sometimes benefit from seeing into tiny spaces that are tricky or impossible to examine without a borescope finds uses for these instruments.

Among the professionals who may rely on borescopes on a daily basis, or at least occasionally, are:

Automotive mechanics
Aerospace engineers
Plumbers
Chimney inspectors
HVAC technicians

What do all these professionals have in common? They all need to get a good look at spaces that are impossible to visually access without the use of a borescope, unless they were to disassemble or break the structures they are working with. With the use of a borescope, it becomes possible to access small spaces hidden from view easily, without the need to take anything apart. This makes borescopes perfect for inspections as well as troubleshooting.

Not every borescope is appropriate for every use, though, and thankfully, an amazing variety of borescopes now graces the market. This makes borescopes accessible and useful to almost everyone — from aerospace engineers who are diagnosing complex problems with priceless aircraft to curious children who simply want to know what the inside of the bathroom sink looks like. (Yes, really, because basic borescopes can cost as little as $30.)

Types of Borescopes: An Overview

Buying a new borescope can be overwhelming, because there are so many different choices. It’s helpful to know that borescopes can broadly be categorized into one of three types:

Rigid borescopes consist of a hollow tube, an eyepiece, light source, and relay lenses, and generally offer an excellent picture quality. Their limitation lies, as the name rigid borescope already suggests, in the fact that they cannot be used to inspect curved or bent areas. Many professionals prefer to use rigid borescopes whenever they can.
Flexible borescopes, also called fiberscopes, rely on optic fiber rather than relay lenses to allow users to get a view of the area they are inspecting. These tubes can be much longer, making flexible borescopes perfect for people who need to access areas that are further away from reachable surfaces. The main advantage of flexible borescopes is that they can be curved in almost any direction, allowing users to view curved pipes and similar areas.
Video borescopes feature tiny cameras (now available fairly cheaply in 320×240 pixel resolutions and above) that allow users to view the area they are inspecting in real time. Video borescopes work with a charged coupled device that sends images to the device’s camera control unit.

Some borescopes, called USB digital borescopes, have WiFi access and USB ports that enable users to attach them to their smartphones or laptops. These USB borescopes have the advantage of being more portable, while also making it possible to easily download the images captured. Some borescopes have LCD screens, while others can even be wireless.

So-called articulating borescopes have probe tips that can point in all directions to make it possible to inspect all areas surrounding the probe. In cases where this is not possible, dual-camera borescopes, which feature two separate lenses, can be helpful.

What Features Can Modern Borescopes Have?

People who are thinking of buying a borescope should keep in mind that not every borescope has the same features. Before you go shopping, it is important to consider what you need:

The diameter of the probe will determine what spaces a borescope can access. Generally speaking, borescopes with smaller probes will be more costly. They may also, on the other hand, offer lower-quality images.
The length of the probe determines how far it will reach.
Some borescopes have a viewing screen, while many modern borescopes directly connect to your computer or phone.
Users who will need to share images captured by the borescope with others (such as home inspectors) will benefit from models that feature media cards.
Many borescopes are waterproof, but this is not universally true. Users who intend to view and inspect areas that are wet or moist, such as plumbers, will need to pay attention to this.
Finally, some borescopes are designed to view objects close-up, while others are made to view areas further away from the camera. It is important to consider this range of focus when shopping for a borescope, too.

While high-resolution industrial borescopes created to be used in manufacturing or aerospace can absolutely cost thousands of dollars, many professionals can now get a borescope that perfectly meets their everyday needs for less than $300 — and if you only need a basic borescope, this handy tool can be yours for less than $100!