How much is the green circle? Explain canon DO lens technology in detail.

Speaking of Canon lens, the first reaction of some readers who are familiar with photography knowledge is its "red circle" lens. Indeed, as a high-end series of Canon lens products, the "red circle" lens has always represented higher optical quality and better mirror body workmanship. However, another high-end series of Canon lenses is far less famous than the "red circle", that is, the "green circle" lens series equipped with Canon DO lens technology. Today I will answer your questions about Canon DO lens technology and "green circle" lens.

Overview of Canon EF 400mm f/4 DO IS II USM products | Pictures (29)| Parameters | Quotation | Comments (2) The local reference reserve price is 46,999.00 yuan.

Let's talk about Canon's lens technology. DO lens is called "diffractive optics", which means "multilayer diffractive optical lens". Compared with the previous fluorite lens and UD lens, this technology has better dispersion elimination performance. The principle of double-layer DO lens independently developed by Canon is to accurately fabricate diffraction grating on the surface of glass lens to form a high-precision laminated structure, thus achieving the purpose of eliminating dispersion.

In its history, the first lens to use DO lens is Canon EF 400mm f/4 DO, which is USM (Big Green), which can also be said to be a sign that Canon DO lens technology really enters the market; In addition to "big green", Canon also has a "little green"-that is, EF 70-300mm f/4.5-5.6 DO is a USM lens; Coupled with the EF 400mm f/4 DO IS II USM updated by Canon in 20 14, Canon has launched three "green circle" lenses. So what are the advantages of DO lenses? Don't worry, everyone. Let's move on.

2 realize the advantages of compact and lightweight telephoto lens.

Realize the advantages of miniaturization and lightweight of telephoto lens.

We know that when the light refracts in the lens, it will produce chromatic aberration and reduce the imaging quality, so in order to compensate it, we need to combine multiple convex mirrors and concave mirror to offset it. Therefore, the general telephoto lens or zoom lens needs to use multiple lenses, which makes the lens bulky and difficult to carry around.

Different from the commonly used technique of correcting chromatic aberration with concave-convex lens combination, DO technique only relies on optical diffraction to eliminate chromatic aberration, so it only needs convex lens, which can not only simplify each lens group in the lens, but also effectively correct other imaging defects except chromatic aberration. For example, Canon EF 400mm f/4 DO IS USM lens (big green) has the same focal length and aperture as Canon EF 400mm f/4 lens, but the length of "big green" is shortened by about 27% and the weight is reduced by about 30%, thus realizing the miniaturization and lightweight of telephoto lens.

In a word, Canon's DO lens technology can eliminate dispersion, aberration and other problems, and at the same time greatly reduce the lens size, making those originally bulky ultra-telephoto lenses small and portable. Therefore, whether it is big green or small green, its size and weight have obvious advantages in the same specifications of the lens. It is precisely because of this that Canon has given the DO lens a striking sign of "green circle". If you have strict requirements on the quality and volume of the lens, then Canon's green circle lens will definitely be your first choice.