Glossary of NIKKOR lens terms

AM | A-M I ARNEOAS | ASED CR | D | DC | E | ED | FC | FL | GHRIIF | M MA ML | Multi-FSN | PF | RD | RF | SIC I SR SSVCM STM | SWM | VR


AM mode (autofocus with manual override, AF priority mode)

An “autofocus-priority autofocus” mode that reduces the sensitivity of the manual override to prevent unexpected switching from auto to manual.
 
A-M switch
An element that locks the focus ring during autofocus while enabling behavior similar to a manual focus lens in manual focus mode with sufficient load when the focusing ring is rotated. The focus rings on the AF-S DX NIKKOR 18-55 mm f/3.5-5.6G VR, AF-S DX Zoom Nikkor ED 18-55 mm f/3.5-5.6G, and AF-S DX Zoom-Nikkor ED 18-55 mm f/3.5-5.6GII rotate during autofocus.

ARNEO - ARNEO Coat
ARNEO Coat is an anti-reflective coating that achieves ultra-low reflectance for incident light reaching the lens surface from a vertical direction. Due to Nikon's original thin-layer manufacturing technology with its optimized algorithm, this system enables the capture of clear and crisp images with minimal ghost and flare, even when a light source is located within the frame.
 
AS - Aspherical lens elements
Nikon introduced the first photographic lens with aspherical lens elements in 1968. What sets them apart? Aspherical lenses virtually eliminate the problem of coma and other types of lens aberration — even when used at the widest aperture. They are particularly useful in correcting the distortion in wide-angle lenses. In addition, the use of aspherical lenses contributes to a lighter and smaller lens design.
Nikon employs three types of aspherical lens elements. Precision-ground aspherical lens elements are the finest expression of lens-crafting art, demanding extremely rigorous production standards. Hybrid lenses are made of a special plastic molded onto optical glass. Molded glass aspherical lenses are manufactured by molding a unique type of optical glass using a special metal die technique.

ASED - Aspherical ED glass
ED (Extra-low Dispersion) glass minimizes colour fringing, aspherical lens features non-spherical surfaces on one or both sides of the glass. It provides superior rendering capability by maximizing the advantages of both ED glass and an aspherical lens – effectively correcting various lens aberrations such as lateral chromatic aberration, coma flare at the periphery, as well as distortion and spherical aberration. It achieves aberration correction of ED glass and aspherical lens in one element, contributing to lens compactness.

CR - Close-Range Correction system
The Close-Range Correction (CRC) system is one of Nikon's most important focusing innovations, for it provides superior picture quality at close focusing distances and increases the focusing range.
With CRC, the lens elements are configured in a “floating element” design wherein each lens group moves independently to achieve focusing. This ensures superior lens performance even when shooting at close distances.
The CRC system is used in fisheye, wide-angle, Micro, and selected medium telephoto NIKKOR lenses.

D - Distance information
D-type and G-type NIKKOR lenses relay subject-to-camera distance information to AF Nikon camera bodies. This then makes possible advances like 3D Matrix Metering and 3D Multi-Sensor Balanced Fill-Flash.
Note: D-type and G-type NIKKOR lenses provide distance information to the following cameras: Auto exposure; F6, F5, F100, F90X, F80, F75, F70, F65, F60, F55, F50, PRONEA S, PRONEA 600i, D2 series, D1 series, D100 and D70s/D70.
Flash control; F6, F5, F100, F90X, F80, F75, F70, D2 series, D1 series, D100 and D70s/D70.

DC - AF DC-NIKKOR lenses — unique NIKKOR lenses for unique portraits
AF DC-NIKKOR lenses feature exclusive Nikon Defocus-image Control technology. This allows photographers to control the degree of spherical aberration in the foreground or background by rotating the lens' DC ring. This will create a rounded out-of-focus blur that is ideal for portrait photography. No other lenses in the world offer this special technique.

E - Electromagnetic Diaphragm Mechanism
An electromagnetic diaphragm mechanism in the lens barrel provides highly accurate electronic diaphragm or aperture blade control when using auto exposure during continuous shooting. With conventional D/G type lenses, the diaphragm blades are operated by mechanical linkage levers.
 
ED glass — an essential element of NIKKOR telephoto lenses
Nikon developed ED (Extra-low Dispersion) glass to enable the production of lenses that offer superior sharpness and color correction by minimizing chromatic aberration.
Put simply, chromatic aberration is a type of image and color dispersion that occurs when light rays of varying wavelengths pass through optical glass. In the past, correcting this problem for telephoto lenses required special optical elements that offer anomalous dispersion characteristics — specifically calcium fluoride crystals. However, fluorite easily cracks and is sensitive to temperature changes that can adversely affect focusing by altering the lens' refractive index.
So Nikon designers and engineers put their heads together and came up with ED glass, which offers all the benefits, yet none of the drawbacks of calcium fluorite-based glass. With this innovation, Nikon developed several types of ED glass suitable for various lenses.
They deliver stunning sharpness and contrast even at their largest apertures. In this way, NIKKOR’s ED-series lenses exemplify Nikon’s preeminence in lens innovation and performance.

FC - Fluorine coat
Nikon's fluorine coat effectively repels dust, water droplets, grease or dirt, ensuring easy removal even when they adhere to the lens surface. Thanks to Nikon's original technology, it delivers higher durability and is more peel-resistant. Compared to other manufacturers' coating of a similar kind, fluorine coat ensures a higher frequency of lens surface wiping and provides longer-duration staying power. Its anti-reflective effect also contributes to the capture of clear images.

FL - Fluorite lens element
Fluorite is a monocrystal optical material that features a high transmission rate within both the infrared and ultraviolet zones. With its superb anomalous dispersion properties, fluorite intensely blocks the secondary spectrum in order to effectively correct chromatic aberration within the visible light spectrum – something that is more difficult to achieve at longer focal lengths. It is also significantly lighter than optical glass, giving you a more effective lens with less weight.

G-type NIKKOR
The G-type NIKKOR has no aperture ring; aperture should be selected from the camera body.

HRI - High Refractive Index lens
With a refractive index of more than 2.0, one HRI lens can offer effects equivalent to those obtained with several normal glass elements and can compensate for both field curvature and spherical aberrations. Therefore, HRI lenses achieve great optical performance in an even more compact body.

IF - Internal Focusing (IF)
Imagine being able to focus a lens without it changing in size. Nikon's IF technology enables just that. All internal optical movement is limited to the interior of the non-extending lens barrel. This allows for a more compact, lightweight construction as well as a closer focusing distance. In addition, a smaller and lighter focusing lens group is employed to ensure faster focusing. The IF system is featured in most NIKKOR telephoto and selected NIKKOR zoom lenses.

MMeso Amorphous Coat
Meso Amorphous Coat suppresses ghost and flare caused by incident light from any direction, including those entering the lens diagonally and vertically, to the utmost limit, demonstrating the highest anti-reflection performance in NIKKOR history. With this coating system, amorphous particles are interconnected and overlapped randomly to create a large number of air gaps termed mesopores. The many gaps within the coating form an ultra-fine mesoporous structure, attaining an outstandingly low refractive index. Additionally, a higher-precision base coat is employed to further enhance the anti-refection effect.

M/A Mode
AF-S NIKKOR lenses feature Nikon's exclusive M/A mode, that allows switching from autofocus to manual operation with virtually no time lag — even during AF servo operation and regardless of AF mode in use.

ML - Meniscus Protective Lens
A curved meniscus protective glass element is installed in front of the lens to minimize ghosting by diffusing light re-reflected from the image sensor or film and the protective glass. Using a meniscus protective lens ensures a clear image with little ghosting.

Multi-FS - Multi-focusing system
A combination of multiple AF drive units provides driving power at high speed and with high accuracy. The position of the focus groups is precisely controlled, resulting in extremely accurate and high-speed AF control. By effectively reducing aberrations, superb imaging performance is delivered across the entire shooting range including close distances.

N - Nano Crystal Coat
Nano Crystal Coat is an antireflective coating that originated in the development of NSR-series (Nikon Step and Repeat) semiconductor manufacturing devices. It virtually eliminates internal lens element reflections across a wide range of wavelengths and is particularly effective in reducing ghost and flare peculiar to ultra- wide-angle lenses. Nano Crystal Coat employs multiple layers of Nikon’s outstanding extra-low refractive index coating, which features ultra-fine crystallized particles of nano size (one nanometer equals one-millionth of a mm ). Nikon now proudly marks a world first by applying this coating technology to a wide range of lenses for use in consumer optical products.

PFPhase Fresnel Lens
The PF (Phase Fresnel) lens, developed by Nikon, effectively compensates chromatic aberration utilizing the photo diffraction phenomenon*. It provides superior chromatic aberration compensation performance when combined with a normal glass lens. Compared to many general camera lenses that employ an optical system using the photorefractive phenomenon, a remarkably compact and lightweight body can be attained with less number of lens elements.
* Diffraction phenomenon: Light has characteristics as a waveform. When a waveform faces an obstacle, it attempts to go around and behind it, and this characteristic is referred to as diffraction. Diffraction causes chromatic dispersion in the reverse order of refraction.

RD - Rounded Diaphragm
Soft-focus shots of point light sources create regular polygonal shapes that reflect the shape of the opening created by the diaphragm blades. A rounded diaphragm uses blades designed to create a circular opening for a more beautiful soft-focus effect.

RF - Rear Focusing (RF)
With Nikon's Rear Focusing (RF) system, all the lens elements are divided into specific lens groups, with only the rear lens group moving for focusing. This makes autofocusing operation smoother and faster.

SIC - Nikon Super Integrated Coating ensures exceptional performance
To enhance the performance of its optical lens elements, Nikon employs an exclusive multilayer lens coating that helps reduce ghost and flare to a negligible level.
Nikon Super Integrated Coating achieves a number of objectives, including minimized reflection in the wider wavelength range and superior color balance and reproduction. Nikon Super Integrated Coating is especially effective for lenses with a large number of elements, like our Zoom-NIKKOR lenses.
Also, Nikon's multilayer coating process is tailored to the design of each particular lens. The number of coatings applied to each lens element is carefully calculated to match the lens type and glass used, and also to assure the uniform color balance that characterizes NIKKOR lenses. This results in lenses that meet much higher standards than the rest of the industry.

SR - SR lens
Nikon's original SR (Short-wavelength Refractive) lens is a high- and specialized-dispersion glass lens featuring characteristics to greatly refract light with wavelengths shorter than that of blue. By controlling short-wavelength light that is difficult to compensate, the light of various specific wavelengths can be more effectively collected achieving highly precise chromatic aberration compensation. Because this lens can be used in the same way as normal glass lenses, a more flexible optical design is attained without limitations in lens layout. While realizing high optical performance, a compact and light lens can be designed.

SSVCMSilky Swift VCM
Silky Swift VCM (SSVCM) is a new AF drive actuator that combines a VCM (voice coil motor) and a new guide mechanism developed by Nikon. The advanced guide mechanism incorporates guide parts between the lens chamber and where the guide bar touches to minimize gaps to the limit, effectively eliminating vibration within the AF drive. Utilizing advantageous features such as this, the superb AF drive system simultaneously delivers higher-speed, higher-accuracy and quieter AF operation, realizing unprecedented AF performance. Even heavy lenses can be controlled precisely at high speed and with minimum noise or vibration. This enables users to reliably capture sharply focused images of decisive moments while also contributing to extremely quiet shooting in both stills and video.

STM - Stepping Motor
The lens autofocus motor operation is synchronized with pulse electric power, rotating one step per electric pulse. It offers high response and controllability for starting and stopping, and its simple mechanical structure allows for extremely quiet operation. Useful for video shooting and at other times when operational noise from the lens is a concern.
Nb. The number of compatible DSLR cameras is limited with AF-P lenses. Even for compatible cameras, some models may require a firmware update. Z NIKKOR lenses with built-in autofocus all use stepping motors.

SWM - Silent Wave Motor
Nikon's AF-S technology is yet another reason professional photographers like NIKKOR telephoto lenses. AF-S NIKKOR lenses feature Nikon’s SWM which converts “traveling waves” into rotational energy to focus the optics. This enables high-speed autofocusing that’s extremely accurate and super quiet.

VR - Vibration Reduction (VR)
This innovative VR system minimizes image blur caused by camera shake, and offers the equivalent of shooting at a shutter speed three stops (eight times) faster.* It allows handheld shooting at dusk, at night, and even in poorly lit interiors. The lens’ VR system also detects automatically when the photographer pans — no special mode is required.
* As determined by Nikon performance tests.

Contact Customer Support