What Is an Image Intensifier?
An image intensifier is a device that detects extremely weak light or X-rays and amplifies them thousands to tens of thousands of times to make them visible.
Image intensifiers intensify and express light rays. Among these devices are, “X-ray image intensifiers” which visualize X-rays, and “MCP image intensifiers” which visualize weak light such as fluorescence, etc.
Since fluorescence and nighttime light are extremely weak, they are converted to electrons and then electrically amplified to create a contrast that make them appear like an image.
Uses of Image Intensifiers
When you hear the word “X-ray,” you probably think of medical X-rays. Of course they are also used in this case. However, image intensifiers are often used because they can visualize X-rays in the form of an image by simply exposing the patient to very weak X-rays, and they can also view X-rays in real-time.
MCP image intensifiers are also used in fluorescence imaging equipment for fluorescent staining of cells.
Principle of Image Intensifiers
An image intensifier is a device, but what is its inner structure?
An image intensifier consists of three components: a photocathode, which receives light; a device, which amplifies electrons; and a fluorescent surface, which reflects the amplified electrons.
We will now explain the principle using an MCP image intensifier as an example.
Normally, when an MCP image intensifier detects light reflected on the photocathode, the light is converted into electrons. The electrons are then amplified in a microchannel plate, and the image produced when they hit the phosphor that serves as the screen is output as an image.
In the case of X-ray image intensifiers, the conversion from X-rays to electrons occurs at a photocathode. The electrons are further accelerated and focused by the focus electrode and anode power supply to obtain an image.
In this way, the conversion to electrons is performed by a device that matches the fluorescence and X-rays, and the human eye sees the amplified image as a visible image.