Information about Light Meter
A light meter is a device used to measure the amount of light. In photography, a light meter is often used to determine the proper exposure for a photograph. Typically a light meter will include a computer, either digital or analogue, which allows the photographer to determine which shutter speed and f-number should be selected for an optimum exposure, given a certain lighting situation and film speed.
Light meters are also used in the fields of cinematography and scenic design, in order to determine the optimum light level for a scene. They are used in the general field of lighting, where they can help to reduce the amount of waste light used in the home, light pollution outdoors, and plant growing to ensure proper light levels.
The earliest type of light meters were called extinction meters and contained a numbered or lettered row of neutral density filters of increasing density. The photographer would position the meter in front of their subject and note the filter with the greatest density which would still allowed incident light to pass through. The letter or number corresponding to the filter was used as an index into a chart of appropriate aperture and shutter speed combinations for a given film speed.
Extinction meters suffered from the problem that they depended on the light sensitivity of the human eye (which can vary from person to person) and subjective interpretation.
Later meters removed the human element and relied on technologies incorporating selenium, CdS, and silicon photosensors.
Selenium and silicon light meters use sensors that are photovoltaic. These sensors generate a voltage proportional to light exposure. Selenium sensors generate enough voltage for direct connection to a meter. Silicon sensors need an amplification circuit and require a power source such as batteries to operate. CdS light meters use a sensor based on photoresistance. These also require a battery to operate. Most modern light meters use silicon or CdS sensors. They indicate the exposure either with a needle galvanometer or on a LCD screen.
Many modern consumer still and video cameras include a built-in meter that measures a scene-wide light level and are able to make an approximate measure of appropriate exposure based on that. Professional photographers and motion picture cinematographers generally use handheld ambient-light meters to precisely measure the light falling on various parts of their subjects and use suitable lighting to produce the desired exposure levels.
There are two general types of ambient-light meters: reflected-light and incident-light. Reflected-light meters measure the light reflected by the scene to be photographed. All in-camera meters are reflected-light meters. Reflected-light meters are calibrated to show the appropriate exposure for “average” scenes. An unusual scene with a preponderance of light colors or specular highlights would have a higher reflectance; a reflected-light meter taking a reading would incorrectly compensate for the difference in reflectance and lead to underexposure.
This pitfall is avoided by incident-light meters which measure the amount of light falling on the subject using an integrating sphere (usually, a translucent hemispherical plastic dome is used to approximate this). Because the incident-light reading is independent of the subject's reflectance, it is less likely to lead to incorrect exposures for subjects with unusual average reflectance. Taking an incident-light reading requires placing the meter at the subject's position and pointing it in the general direction of the camera, something not always achievable in practice, e.g., in landscape photography where the subject is at infinity.
Another way to avoid under- or over-exposure for subjects with unusual reflectance is to use a spot meter: a reflected-light meter that measures light in a very tight cone, typically with a one degree angle. An experienced photographer can take multiple readings over the shadows, midrange and highlights of the scene to determine optimal exposure, using systems like the Zone System. Many modern cameras include sophisticated multi-segment metering systems that measure the luminance of different parts of the scene and use various algorithms to determine optimal exposure.
When using orthochromatic black and white or infrared film that is not sensitive to the entire visible light spectrum, a light meter may require special filters and re-calibration to match the sensitivity of the film.
There are other types of specialized photographic light meters. Flash meters are used in flash photography to verify correct exposure. Color meters are used where high fidelity in color reproduction is required. Densitometers are used in photographic reproduction.
Meter calibration establishes the relationship between subject lighting and recommended camera settings. The calibration of photographic light meters is covered by .
where
where
In practice, the variation of the calibration constants among manufacturers is considerably less than this statement might imply, and values have changed little since the early 1970s.
recommends a range for
of 10.6 to 13.4 with
luminance in cd/m². Two values for are in common
use: 12.5 (Canon, Nikon, and
Sekonic[1]) and 14 (Minolta and Pentax); the
difference between the two values is approximately 1/6
EV.
Common practice when calibration standards were first developed was to use wide-angle averaging reflected-light meters. Although wide-angle average metering has largely given way to other metering sensitivity patterns (e.g., spot, center-weighted, and multi-segment), the values for determined for wide-angle averaging meters have remained.
The incident-light calibration constant depends on the type of light receptor. Two receptor types are common: flat (cosine-responding) and hemispherical (cardioid-responding). With a flat receptor, recommends a range for
of 240 to 400 with
illuminance in lux; a value of 250 is commonly used. A flat receptor
typically is used for measurement of lighting ratios, for measurement of
illuminance, and occasionally, for determining exposure for a flat subject.
For determining practical photographic exposure, a hemispherical receptor has proven more effective. Don Norwood, inventor of incident-light exposure meter with a hemispherical receptor, thought that a sphere was a reasonable representation of a photographic subject; according to his patent, the objective was
and the meter provided for
With a hemispherical receptor, recommends a range for of 320 to 540 with illuminance in lux; in practice, values
typically are between 320 (Minolta) and 340 (Sekonic). The relative
responses of flat and hemispherical receptors depend upon the number and type
of light sources; when each receptor is pointed at a small light
source, a hemispherical receptor with = 330 will indicate an
exposure approximately 0.40 step greater than that indicated by a flat
receptor with = 250. With a slightly revised definition of illuminance,
measurements with a hemispherical receptor indicate “effective scene
illuminance.?
Combining the reflected-light and incident-light exposure equations and rearranging gives
Reflectance
is defined as
A uniform perfect diffuser (i.e., one following Lambert's cosine law) of luminance
emits a flux density of
; reflectance then is
Illuminance is measured with a flat receptor. It is straightforward to compare an incident-light measurement using a flat receptor with a reflected-light measurement of a uniformly illuminated flat surface of constant reflectance. Using values of 12.5 for and 250 for
gives
With a of 14, the reflectance would be 17.6%, close to that
of a standard 18% neutral test card. In theory, an incident-light
measurement should agree with a reflected-light measurement of a test card
of suitable reflectance that is perpendicular to the direction to the
meter. However, a test card seldom is a uniform diffuser, so incident- and
reflected-light measurements might differ slightly.
In a typical scene, many elements are not flat and are at various orientations to the camera, so that for practical photography, a hemispherical receptor usually has proven more effective for determining exposure. Using values of 12.5 for and 330 for gives
With a slightly revised definition of reflectance, this result can be taken as indicating that the average scene reflectance is approximately 12%. A typical scene includes shaded areas as well as areas that receive direct illumination, and a wide-angle averaging reflected-light meter responds to these differences in illumination as well as differing reflectances of various scene elements. Average scene reflectance then would be
where “effective scene illuminance” is that measured by a meter with a hemispherical receptor.
calls for reflected-light calibration to be measured by aiming the receptor at a transilluminated diffuse surface, and for incident-light calibration to be measured by aiming the receptor at a point source in a darkened room. For a perfectly diffusing test card and perfectly diffusing flat receptor, the comparison between a reflected-light measurement and an incident-light measurement is valid for any position of the light source. However, the response of a hemispherical receptor to an off-axis light source is approximately that of a cardioid rather than a cosine, so the 12% “reflectance” determined for an incident-light meter with a hemispherical receptor is valid only when the light source is on the receptor axis., and many calibration instruments
(e.g., Kyoritsu-Arrowin multi-function camera testers[2] ) use the specified
to set the test parameters.
The instructions for a Kodak neutral test card recommend that the indicated exposure be increased by ½ step for a frontlighted scene in sunlight. The instructions also recommend that the test card be held vertically and faced in a direction midway between the Sun and the camera; similar directions are also given in the Kodak Professional Photoguide. The combination of exposure increase and the card orientation gives recommended exposures that are reasonably close to those given by an incident-light meter with a hemispherical receptor when metering with an off-axis light source.
In practice, additional complications may arise. Many neutral test cards are far from perfectly diffuse reflectors, and specular reflections can cause increased reflected-light meter readings that, if followed, would result in underexposure. It is possible that the neutral test card instructions include a correction for specular reflections.
Light meters are also used in the fields of cinematography and scenic design, in order to determine the optimum light level for a scene. They are used in the general field of lighting, where they can help to reduce the amount of waste light used in the home, light pollution outdoors, and plant growing to ensure proper light levels.
Use in Photography
)
A handheld digital ambient light meter, showing an f-stop of 5.6 for 24 frame/s 500 ISO filming
The earliest type of light meters were called extinction meters and contained a numbered or lettered row of neutral density filters of increasing density. The photographer would position the meter in front of their subject and note the filter with the greatest density which would still allowed incident light to pass through. The letter or number corresponding to the filter was used as an index into a chart of appropriate aperture and shutter speed combinations for a given film speed.
Extinction meters suffered from the problem that they depended on the light sensitivity of the human eye (which can vary from person to person) and subjective interpretation.
Later meters removed the human element and relied on technologies incorporating selenium, CdS, and silicon photosensors.
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){kind=small}
Selenium and silicon light meters use sensors that are photovoltaic. These sensors generate a voltage proportional to light exposure. Selenium sensors generate enough voltage for direct connection to a meter. Silicon sensors need an amplification circuit and require a power source such as batteries to operate. CdS light meters use a sensor based on photoresistance. These also require a battery to operate. Most modern light meters use silicon or CdS sensors. They indicate the exposure either with a needle galvanometer or on a LCD screen.
Many modern consumer still and video cameras include a built-in meter that measures a scene-wide light level and are able to make an approximate measure of appropriate exposure based on that. Professional photographers and motion picture cinematographers generally use handheld ambient-light meters to precisely measure the light falling on various parts of their subjects and use suitable lighting to produce the desired exposure levels.
There are two general types of ambient-light meters: reflected-light and incident-light. Reflected-light meters measure the light reflected by the scene to be photographed. All in-camera meters are reflected-light meters. Reflected-light meters are calibrated to show the appropriate exposure for “average” scenes. An unusual scene with a preponderance of light colors or specular highlights would have a higher reflectance; a reflected-light meter taking a reading would incorrectly compensate for the difference in reflectance and lead to underexposure.
This pitfall is avoided by incident-light meters which measure the amount of light falling on the subject using an integrating sphere (usually, a translucent hemispherical plastic dome is used to approximate this). Because the incident-light reading is independent of the subject's reflectance, it is less likely to lead to incorrect exposures for subjects with unusual average reflectance. Taking an incident-light reading requires placing the meter at the subject's position and pointing it in the general direction of the camera, something not always achievable in practice, e.g., in landscape photography where the subject is at infinity.
Another way to avoid under- or over-exposure for subjects with unusual reflectance is to use a spot meter: a reflected-light meter that measures light in a very tight cone, typically with a one degree angle. An experienced photographer can take multiple readings over the shadows, midrange and highlights of the scene to determine optimal exposure, using systems like the Zone System. Many modern cameras include sophisticated multi-segment metering systems that measure the luminance of different parts of the scene and use various algorithms to determine optimal exposure.
When using orthochromatic black and white or infrared film that is not sensitive to the entire visible light spectrum, a light meter may require special filters and re-calibration to match the sensitivity of the film.
There are other types of specialized photographic light meters. Flash meters are used in flash photography to verify correct exposure. Color meters are used where high fidelity in color reproduction is required. Densitometers are used in photographic reproduction.
Exposure meter calibration
In most cases, an incident-light meter will cause a medium tone to be recorded as a medium tone, and a reflected-light meter will cause whatever is metered to be recorded as a medium tone. What constitutes a “medium tone” depends on meter calibration and several other factors, including film processing or digital image conversion.Meter calibration establishes the relationship between subject lighting and recommended camera settings. The calibration of photographic light meters is covered by .
Exposure equations
For reflected-light meters, camera settings are related to ISO speed and subject luminance by the reflected-light exposure equation:
where
is the relative aperture (f-number)
is the exposure time (“shutter speed”)
- is the average scene luminance
is the ISO linear speed
- is the reflected-light meter calibration constant
where
is the illuminance
- is the incident-light meter calibration constant
Calibration constants
Determination of calibration constants has been largely subjective; states that“The constants
In practice, the variation of the calibration constants among manufacturers is considerably less than this statement might imply, and values have changed little since the early 1970s.
recommends a range for
of 10.6 to 13.4 with
luminance in cd/m². Two values for are in common
use: 12.5 (Canon, Nikon, and
Sekonic[1]) and 14 (Minolta and Pentax); the
difference between the two values is approximately 1/6
EV.
Common practice when calibration standards were first developed was to use wide-angle averaging reflected-light meters. Although wide-angle average metering has largely given way to other metering sensitivity patterns (e.g., spot, center-weighted, and multi-segment), the values for
determined for wide-angle averaging meters have remained.
The incident-light calibration constant depends on the type of light receptor. Two receptor types are common: flat (cosine-responding) and hemispherical (cardioid-responding). With a flat receptor, recommends a range for
of 240 to 400 with
illuminance in lux; a value of 250 is commonly used. A flat receptor
typically is used for measurement of lighting ratios, for measurement of
illuminance, and occasionally, for determining exposure for a flat subject.
For determining practical photographic exposure, a hemispherical receptor has proven more effective. Don Norwood, inventor of incident-light exposure meter with a hemispherical receptor, thought that a sphere was a reasonable representation of a photographic subject; according to his patent, the objective was
“to provide an exposure meter which is substantially uniformly responsive to light incident upon the photographic subject from practically all directions which would result in the reflection of light to the camera or other photographic register.?
and the meter provided for
“measurement of the effective illumination obtaining at the position of the subject.?
With a hemispherical receptor, recommends a range for
of 320 to 540 with illuminance in lux; in practice, values
typically are between 320 (Minolta) and 340 (Sekonic). The relative
responses of flat and hemispherical receptors depend upon the number and type
of light sources; when each receptor is pointed at a small light
source, a hemispherical receptor with = 330 will indicate an
exposure approximately 0.40 step greater than that indicated by a flat
receptor with = 250. With a slightly revised definition of illuminance,
measurements with a hemispherical receptor indicate “effective scene
illuminance.?
Calibrated reflectance
It is commonly stated that reflected-light meters are calibrated to an 18% (sometimes, 12%) reflectance, but the calibration has nothing to do with reflectance, as should be evident from the exposure formulae. However, some notion of reflectance is implied by a comparison of incident- and reflected-light meter calibration.Combining the reflected-light and incident-light exposure equations and rearranging gives
Reflectance
is defined as
A uniform perfect diffuser (i.e., one following Lambert's cosine law) of luminance
emits a flux density of
; reflectance then is
Illuminance is measured with a flat receptor. It is straightforward to compare an incident-light measurement using a flat receptor with a reflected-light measurement of a uniformly illuminated flat surface of constant reflectance. Using values of 12.5 for
and 250 for
gives
With a
of 14, the reflectance would be 17.6%, close to that
of a standard 18% neutral test card. In theory, an incident-light
measurement should agree with a reflected-light measurement of a test card
of suitable reflectance that is perpendicular to the direction to the
meter. However, a test card seldom is a uniform diffuser, so incident- and
reflected-light measurements might differ slightly.
In a typical scene, many elements are not flat and are at various orientations to the camera, so that for practical photography, a hemispherical receptor usually has proven more effective for determining exposure. Using values of 12.5 for
and 330 for gives
With a slightly revised definition of reflectance, this result can be taken as indicating that the average scene reflectance is approximately 12%. A typical scene includes shaded areas as well as areas that receive direct illumination, and a wide-angle averaging reflected-light meter responds to these differences in illumination as well as differing reflectances of various scene elements. Average scene reflectance then would be
where “effective scene illuminance” is that measured by a meter with a hemispherical receptor.
calls for reflected-light calibration to be measured by aiming the receptor at a transilluminated diffuse surface, and for incident-light calibration to be measured by aiming the receptor at a point source in a darkened room. For a perfectly diffusing test card and perfectly diffusing flat receptor, the comparison between a reflected-light measurement and an incident-light measurement is valid for any position of the light source. However, the response of a hemispherical receptor to an off-axis light source is approximately that of a cardioid rather than a cosine, so the 12% “reflectance” determined for an incident-light meter with a hemispherical receptor is valid only when the light source is on the receptor axis.
Cameras with internal meters
Calibration of cameras with internal meters is covered by ; nonetheless, many manufacturers specify (though seldom state) exposure calibration in terms of, and many calibration instruments
(e.g., Kyoritsu-Arrowin multi-function camera testers[2] ) use the specified
to set the test parameters.
Exposure determination with a neutral test card
If a scene differs considerably from a statistically average scene, a wide-angle averaging reflected-light measurement may not indicate the correct exposure. To simulate an average scene, a substitute measurement sometimes is made of a neutral test card, or gray card.The instructions for a Kodak neutral test card recommend that the indicated exposure be increased by ½ step for a frontlighted scene in sunlight. The instructions also recommend that the test card be held vertically and faced in a direction midway between the Sun and the camera; similar directions are also given in the Kodak Professional Photoguide. The combination of exposure increase and the card orientation gives recommended exposures that are reasonably close to those given by an incident-light meter with a hemispherical receptor when metering with an off-axis light source.
In practice, additional complications may arise. Many neutral test cards are far from perfectly diffuse reflectors, and specular reflections can cause increased reflected-light meter readings that, if followed, would result in underexposure. It is possible that the neutral test card instructions include a correction for specular reflections.
Use in illumination
Light meters or light detectors are also used in illumination. Their purpose is to measure the illumination level in the interior and to switch off or reduce the output level of luminaires. They can greatly reduce the energy burden of the building by significantly increasing the efficiency of lighting system. It is known, that 20 to 60 percent of all electrical power in a building is consumed by illumination. It is therefore recommended to use light meters in lighting systems especially in rooms, where one cannot expect users to pay attention to manual switching off the lights. These are: hallways, stairs, big halls etc. There are, however, significant obstacles to overcome in order to achieve a successful implementation of light meters in lighting systems, of which user-acceptance is by far the most formidable. Unexpected or too frequent switching and too bright or too dark rooms are very annoying and disturbing for users of the rooms. Therefore, different switching algorithms have been developed:- difference algorithm, where light switch on lower light level than they switch off, thus taking care that the difference between the light level of the 'on' state and 'off' state is not too big
- time delay algorithms:
- certain amount of time must pass since the last switch
- certain amount of time of sufficient illumination.
Notes
1. ^ Specifications for Sekonic light meters are available on the Sekonic web site under “Products.”
2. ^ Specifications for Kyoritsu testers are available on the C.R.I.S. Camera Services web site under “kyoritsu test equipment.”
2. ^ Specifications for Kyoritsu testers are available on the C.R.I.S. Camera Services web site under “kyoritsu test equipment.”
References
- Eastman Kodak Company. Instructions for Kodak Neutral Test Card, 453-1-78-ABX. Rochester: Eastman Kodak Company
- Eastman Kodak Company. 1992. Kodak Professional Photoguide. Kodak publication no. R-28. Rochester: Eastman Kodak Company
- ISO 2720:1974. General Purpose Photographic Exposure Meters (Photoelectric Type) —Guide to Product Specification. International Organization for Standardization
- ISO 2721:1982. Photography — Cameras — Automatic controls of exposure. International Organization for Standardization
- Norwood, Donald W. 1938. Exposure Meter. US Patent 2,214,283, filed 14 November 1938, and issued 10 September 1940
See also
- Light value
- Lighting design
- Photometry (optics) Main Photometry/Radiometry article - explains technical terms
- Photomultiplier tube
- PIN diode
- Radiometer
External links
- Meters Don't See 18% Gray An article suggesting that photographic light meters are calibrated for 12% average reflectance.
- Exposure Metering: Relating Subject Lighting to Film Exposure (PDF) A discussion of meter calibration and its practical effects.
- A Kodak guide to Estimating Luminance and Illuminance using a camera's exposure meter. Also available in PDF.
Photography [fә'tɑgrәfi:],[foʊ'tɑgrәfi:] is the process of recording pictures by means of capturing light on a light-sensitive medium, such as a film or electronic sensor.
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exposure is the total amount of light allowed to fall on the photographic medium (photographic film or image sensor) during the process of taking a photograph. Exposure is measured in lux seconds, and can be computed from exposure value (EV) and scene luminance.
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shutter speed is the length of time a shutter is open; the total exposure is proportional to this exposure time, or duration of light reaching the film or image sensor.
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f-number (sometimes called focal ratio, f-ratio, or relative aperture[1]) of an optical system expresses the diameter of the entrance pupil in terms of the effective focal length of the lens.
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Film speed is the measure of a photographic film's sensitivity to light. Stock with lower sensitivity (lower ISO speed rating) requires a longer exposure and is thus called a slow film
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Cinematography (from Greek: kinesis (movement) and grapho (to record)), is the discipline of making lighting and camera choices when recording photographic images for the cinema.
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Scenic design (also known as stage design, set design or production design) is the creation of theatrical scenery. Scenic designers have traditionally come from a variety of artistic backgrounds, but nowadays, generally speaking, they are trained professionals, often with M.F.A.
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Illumination might refer to:
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- Artistry
- Illumination (lighting)
- Illumination (image), presenting effects of lighting in drawings, paintings, etc.
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Light pollution is excess or obtrusive light created by humans. Among other effects, it disrupts ecosystems, can cause adverse health effects, obscures the stars for city dwellers, interferes with astronomical observatories, and wastes energy.
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neutral density filter or ND filter is a "grey" filter. An ideal neutral density filter reduces light of all wavelengths or colors equally. The purpose of standard photographic neutral density filters is to allow the photographer greater flexibility to change the aperture or
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Film speed is the measure of a photographic film's sensitivity to light. Stock with lower sensitivity (lower ISO speed rating) requires a longer exposure and is thus called a slow film
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4, 6
(strongly acidic oxide)
Electronegativity 2.55 (scale Pauling)
Ionization energies
(more) 1st: 941.0 kJmol−1
2nd: 2045 kJmol−1
3rd: 2973.
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(strongly acidic oxide)
Electronegativity 2.55 (scale Pauling)
Ionization energies
(more) 1st: 941.0 kJmol−1
2nd: 2045 kJmol−1
3rd: 2973.
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Cadmium sulfide is a chemical compound with the formula CdS. It exists in nature as two different minerals, greenockite and hawleyite.
Greenockite forms hexagonal crystals with the wurtzite structure. It has a yellowish colour with specific gravity of 4.
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Greenockite forms hexagonal crystals with the wurtzite structure. It has a yellowish colour with specific gravity of 4.
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Silicon (IPA: /ˈsɪlɪkən/ or /ˈsɪlɪˌkɑn/, Latin: silicium
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Photovoltaics, or PV for short, is a solar power technology that uses solar cells or solar photovoltaic arrays to convert light from the sun directly into electricity.
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battery is a device consisting of one or more electrochemical cells, which store chemical energy and make it available in an electrical form. There are many types of electrochemical cells, including galvanic cells, electrolytic cells, fuel cells, flow cells, and voltaic cells.
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photoresistor or LDR is an electronic component whose resistance decreases with increasing incident light intensity. It can also be referred to as a light-dependent resistor (LDR), photoconductor, or photocell.
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galvanometer is a type of ammeter — an instrument for detecting and measuring electric current. It is an electromechanical transducer that produces a rotary deflection, through a limited arc, in response to electric current flowing through its coil.
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liquid crystal display (commonly abbreviated LCD) is a thin, flat display device made up of any number of color or monochrome pixels arrayed in front of a light source or reflector.
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camera is a device used to capture images, as still photographs or as sequences of moving images (movies or videos). The term as well as the modern-day camera evolved from the camera obscura
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cinematographer is one photographing with a motion picture camera (the art and science of which is known as cinematography). The title is generally equivalent to director of photography
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The Zone System is a photographic technique for determining optimal film exposure and development, formulated by Ansel Adams and Fred Archer in 1941. The Zone System provides photographers with a systematic method of precisely defining the relationship between the way they
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In optics, an aperture is a hole or an opening through which light is admitted. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane.
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f-number (sometimes called focal ratio, f-ratio, or relative aperture[1]) of an optical system expresses the diameter of the entrance pupil in terms of the effective focal length of the lens.
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shutter speed is the length of time a shutter is open; the total exposure is proportional to this exposure time, or duration of light reaching the film or image sensor.
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Luminance is a photometric measure of the density of luminous intensity in a given direction. It describes the amount of light that passes through or is emitted from a particular area, and falls within a given solid angle.
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Film speed is the measure of a photographic film's sensitivity to light. Stock with lower sensitivity (lower ISO speed rating) requires a longer exposure and is thus called a slow film
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illuminance is the total luminous flux incident on a surface, per unit area. It is a measure of the intensity of the incident light, wavelength-weighted by the luminosity function to correlate with human brightness perception.
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Canon Inc.
Public (TYO: 7751 , NYSE: CAJ )
Founded Tokyo, Japan (August 10, 1937)
Headquarters Tokyo, Japan
Key people Fujio Mitarai, Chairman & CEO
Tsuneji Uchida, President & COO
Industry Imaging
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Public (TYO: 7751 , NYSE: CAJ )
Founded Tokyo, Japan (August 10, 1937)
Headquarters Tokyo, Japan
Key people Fujio Mitarai, Chairman & CEO
Tsuneji Uchida, President & COO
Industry Imaging
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Nikon Corporation
株式会社ニコン
Corporation TYO: 7731
Founded Tokyo, Japan (1917)
Headquarters Tokyo, Japan
Key people Michio Kariya, President, CEO & COO
Industry Imaging
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株式会社ニコン
Corporation TYO: 7731
Founded Tokyo, Japan (1917)
Headquarters Tokyo, Japan
Key people Michio Kariya, President, CEO & COO
Industry Imaging
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