JP2011204643A - Lighting system - Google Patents

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JP2011204643A
JP2011204643A JP2010073579A JP2010073579A JP2011204643A JP 2011204643 A JP2011204643 A JP 2011204643A JP 2010073579 A JP2010073579 A JP 2010073579A JP 2010073579 A JP2010073579 A JP 2010073579A JP 2011204643 A JP2011204643 A JP 2011204643A
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brightness
value
lighting
sensitivity
pixel value
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Junro Nanahara
淳郎 七原
Shinji Matsuda
真二 松田
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Panasonic Electric Works Co Ltd
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Panasonic Electric Works Co Ltd
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y02B20/40—Control techniques providing energy savings, e.g. smart controller or presence detection

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Abstract

PROBLEM TO BE SOLVED: To provide a lighting system wherein a sensor signal used for dimming control has a designated resolving power, independently of the reflectivity of lighting range.SOLUTION: The lighting system includes a lighting fixture 3, a camera 1 making the lighting range of the lighting fixture 3 as an imaging range, and a lighting control device 2 for adjusting a dimming level of the lighting fixture 3 so as to make the average pixel value calculated from an image signal of the camera 1 have a designated pixel value α. The camera 1 has a γ-characteristic correction means 12 for correcting the γ-characteristic of an image signal from an imaging element 11, and a sensitivity correction means 13 for correcting the sensitivity of output from the γ-characteristic correction means 12. The γ-characteristic correction means 12 and the sensitivity correction means 13 are controlled so that the average pixel value of the image signal output from the camera 1 have the pixel value α; and the average pixel value to brightness of the lighting range is in direct proportion, when the lighting range is established as comfortable brightness.

Description

本発明は、照明システムに関するものである。   The present invention relates to a lighting system.

従来、例えばフォトダイオードなどの明るさセンサによって照明器具による照明領域の明るさを検知し、照明器具の調光レベルを調整することで照明領域の明るさを一定に保つ照明システムが提供されている。   2. Description of the Related Art Conventionally, there has been provided an illumination system that keeps the brightness of an illumination area constant by detecting the brightness of an illumination area by a lighting fixture using a brightness sensor such as a photodiode and adjusting the dimming level of the lighting fixture. .

この種の照明システムにおいては、まず初期設定として、予め外光の入射しない環境で照明領域が適切な明るさとなるように照明器具の光出力を設定し、その時のフォトダイオードからの出力電圧を目標値として不揮発性メモリなどに記憶させる。その後、実際に運用が開始され、外光が窓から入射して照明領域が明るくなると、フォトダイオードからの出力電圧が上昇するので、照明制御回路によって照明器具の調光レベルを下げるよう制御が行われる。また、窓から外光が入射しなくなって照明領域が暗くなると、フォトダイオードからの出力電圧が低下するので、照明制御回路によって照明器具の調光レベルを上げるよう制御が行われる。これらの制御を目標値から所定の誤差範囲（通常、数％程度）に収まるまで行うことで、適切な明るさを保つようにしている。   In this type of lighting system, as an initial setting, the light output of the luminaire is set in advance so that the illumination area has an appropriate brightness in an environment where no external light is incident, and the output voltage from the photodiode at that time is set as a target. The value is stored in a nonvolatile memory or the like. After that, when the operation is actually started and the illumination area becomes brighter when external light enters from the window, the output voltage from the photodiode increases, so the lighting control circuit controls the lighting device to lower the dimming level. Is called. Further, when the outside light is no longer incident from the window and the illumination area becomes dark, the output voltage from the photodiode is lowered. Therefore, the illumination control circuit performs control to increase the dimming level of the luminaire. By performing these controls from the target value until it falls within a predetermined error range (usually about several percent), appropriate brightness is maintained.

ところで、フォトダイオードからの出力電圧は、照明領域の明るさが同じ場合であっても、被照射面の反射率が違えば、異なる出力電圧となる。すなわち、照明領域の反射率が高い場合には出力電圧は高く、反射率が低い場合には出力電圧が低くなる。ここで出力電圧が高くなると、照明制御回路にて処理可能な信号レベルを超える可能性があり、また、出力電圧が低くなると、照明制御回路における分解能が低下して、正常に調光レベルの制御を行うことが出来ない可能性がある。   By the way, even if the brightness of the illumination region is the same, the output voltage from the photodiode becomes a different output voltage if the reflectance of the irradiated surface is different. That is, when the reflectance of the illumination area is high, the output voltage is high, and when the reflectance is low, the output voltage is low. When the output voltage increases, the signal level that can be processed by the lighting control circuit may be exceeded. When the output voltage decreases, the resolution in the lighting control circuit decreases, and the dimming level is controlled normally. May not be possible.

そこで、この種の照明システムでは、フォトダイオードからの出力電圧のゲインを制御し、照明制御回路に入力される信号レベルが正常な範囲に収まるよう調整している。具体的には、図７に示すように、まず最も高いゲインであるゲインｇ１でフォトダイオードからの出力電圧を測定し、この値が所定値を超えている場合には、ゲインｇ１よりも低いゲインに設定されたゲインｇ２で出力電圧の測定を行う。ゲインｇ２でも出力電圧が所定値を超える場合には、さらに低いゲインに設定されたゲインｇ３で出力電圧の測定を行い、照明制御回路が処理可能な信号レベルの信号を入力する。このようにすることで、反射率や目標とする明るさが異なる場合であっても、適切な明るさに照明領域が保たれている。   Therefore, in this type of illumination system, the gain of the output voltage from the photodiode is controlled so that the signal level input to the illumination control circuit falls within a normal range. Specifically, as shown in FIG. 7, first, the output voltage from the photodiode is measured at the gain g1, which is the highest gain, and if this value exceeds a predetermined value, the gain is lower than the gain g1. The output voltage is measured with the gain g2 set to. If the output voltage exceeds the predetermined value even with the gain g2, the output voltage is measured with the gain g3 set to a lower gain, and a signal having a signal level that can be processed by the illumination control circuit is input. By doing so, the illumination area is maintained at an appropriate brightness even when the reflectance and the target brightness are different.

ところで近年、人体を検知して点灯・消灯の切り替えを実現するため、照明領域に設けられた撮像領域を撮像するカメラを備えた照明システムが提案されている。このような照明システムでは、フォトダイオードのような明るさセンサの代わりとして、カメラを用いて照明領域の明るさを検出して、照明器具の調光レベルが調整されているものもある（例えば、特許文献１）。   By the way, in recent years, an illumination system including a camera that captures an imaging region provided in an illumination region has been proposed in order to detect a human body and realize switching between lighting and extinguishing. In such a lighting system, instead of a brightness sensor such as a photodiode, the brightness of an illumination area is detected using a camera, and the dimming level of the lighting fixture is adjusted (for example, Patent Document 1).

特開２００１−１６２９６７号公報JP 2001-162967 A

ところで、一般的にカメラは、ＣＲＴや液晶パネルなどの表示デバイスと組み合わせて使用することがほとんどである。これらの表示デバイスは、γ特性値が２．０前後であるので、表示デバイスに撮像画像を表示した際に輝度や色合いの再現性を高めることを目的として、一般的なカメラのγ特性値は０．５程度に設定されている。   Incidentally, in general, a camera is mostly used in combination with a display device such as a CRT or a liquid crystal panel. Since these display devices have a γ characteristic value of around 2.0, for the purpose of enhancing the reproducibility of luminance and hue when a captured image is displayed on the display device, the γ characteristic value of a general camera is It is set to about 0.5.

このようなカメラを、上述のような照明システムに用いた場合、照明領域の明るさと撮像画像の平均画素値との関係は正比例にはならず、従来の照明領域の反射率に応じてゲインを段階的に変更する単純な制御を適応することは出来なかった。   When such a camera is used in an illumination system as described above, the relationship between the brightness of the illumination area and the average pixel value of the captured image is not directly proportional, and the gain is set according to the reflectance of the conventional illumination area. A simple control that changes in stages could not be applied.

また、上述のようなゲインを段階的に変更する単純な制御の場合、照明領域の目標とする明るさが同じであっても、目標とするフォトダイオードからの出力電圧は図７のVAとVDのように大きく異なる場合がある。そのため、出力電圧がVBの場合（すなわち、反射率が高い場合）には、目標とする出力電圧がVAの場合（すなわち、反射率が低い場合）と比べて、調光制御回路に入力される入力信号の分解能が低く、上述の誤差範囲が狭くなるという問題があった。   Further, in the case of simple control in which the gain is changed stepwise as described above, the output voltage from the target photodiode is VA and VD in FIG. 7 even if the target brightness of the illumination area is the same. There are cases where it is very different. Therefore, when the output voltage is VB (that is, when the reflectance is high), it is input to the dimming control circuit compared to when the target output voltage is VA (that is, when the reflectance is low). There is a problem that the resolution of the input signal is low and the above-described error range is narrowed.

本発明は、上記事由に鑑みて為されたものであり、その目的とするところは、照明器具によって照明される被照射面の反射率によらず、調光制御に用いられるセンサ信号が所定の分解能を有する照明システムを提供することにある。   The present invention has been made in view of the above-described reasons, and the object of the present invention is that the sensor signal used for dimming control is a predetermined signal regardless of the reflectance of the irradiated surface illuminated by the lighting fixture. It is to provide an illumination system having a resolution.

上記目的を達成するために、第１の発明では、照明器具と、照明器具によって照明される被照射面を撮像して撮像信号を出力する撮像素子と、撮像信号のγ特性を補正するγ特性補正手段と、撮像信号の感度を補正する感度補正手段と、γ特性及び感度の補正がされた映像信号に基づいて、照明器具による照明領域の明るさを示す明るさ指標を出力する明るさ指標生成手段と、明るさ指標が所定の明るさ目標値に対して、所定の範囲内に収まるよう照明器具の調光レベルを制御する照明制御手段とを備え、γ特性補正手段及び感度補正手段は、照明領域の明るさと明るさ指標とが正比例の関係となり、且つ、照明領域が所望の明るさである際に、明るさ指標が明るさ目標値となるよう撮像信号の補正を行うことを特徴とする。   In order to achieve the above object, according to the first aspect of the present invention, there is provided a lighting fixture, an imaging device for imaging an irradiated surface illuminated by the lighting fixture and outputting an imaging signal, and a γ characteristic for correcting the γ characteristic of the imaging signal. A brightness index that outputs a brightness index that indicates the brightness of the illumination area by the luminaire based on the correction means, the sensitivity correction means that corrects the sensitivity of the imaging signal, and the video signal that has been corrected for the γ characteristic and the sensitivity A generation unit, and an illumination control unit that controls a dimming level of the luminaire so that the brightness index is within a predetermined range with respect to a predetermined brightness target value, and the γ characteristic correction unit and the sensitivity correction unit are The imaging signal is corrected so that the brightness index becomes a brightness target value when the brightness of the illumination area is directly proportional to the brightness index and the illumination area has a desired brightness. And

第２の発明では、第１の発明において、明るさ目標値は、明るさ指標の最大値に対して、略５０％の値となるように設定されることを特徴とする。   According to a second aspect, in the first aspect, the brightness target value is set to be a value of about 50% with respect to the maximum value of the brightness index.

本発明によれば、照明器具によって照明される被照射面の反射率によらず、調光制御に用いられるセンサ信号が所定の分解能を有する照明システムを提供することができる。   According to the present invention, it is possible to provide an illumination system in which a sensor signal used for dimming control has a predetermined resolution regardless of the reflectance of an irradiated surface illuminated by a lighting fixture.

本発明の実施の形態にかかる照明システムを示す概略ブロック図である。It is a schematic block diagram which shows the illumination system concerning embodiment of this invention. 同照明システムの設置例を示す概略図である。It is the schematic which shows the example of installation of the illumination system. 同照明システムにおける初期設定前の照明領域の明るさとカメラからの出力との関係を示すグラフである。It is a graph which shows the relationship between the brightness of the illumination area | region before the initial setting in the illumination system, and the output from a camera. 同照明システムにおけるγ特性値を補正する補正方法を説明するためのグラフである。It is a graph for demonstrating the correction method which correct | amends (gamma) characteristic value in the same illumination system. 同照明システムにおける初期設定の動作を説明するためのグラフである。It is a graph for demonstrating the operation | movement of the initial setting in the illumination system. 同照明システムにおける初期設定の動作を説明するためのグラフである。It is a graph for demonstrating the operation | movement of the initial setting in the illumination system. 従来の照明システムにおける動作を説明するためのグラフである。It is a graph for demonstrating operation | movement in the conventional illumination system.

以下に本発明の実施の形態を図面（図１〜図６）に基づいて説明を行う。   Embodiments of the present invention will be described below with reference to the drawings (FIGS. 1 to 6).

本実施の形態にかかる照明システムは、図２に示すように、例えば天井面に設置され下方を照明領域とする照明器具３と、照明領域の一部を撮像領域とするカメラ１と、カメラ１からの出力に基づいて照明器具３を制御する照明制御装置２とを備える。   As shown in FIG. 2, the lighting system according to the present embodiment includes, for example, a lighting fixture 3 that is installed on a ceiling surface and has a lower illumination area, a camera 1 that has a part of the illumination area as an imaging area, and a camera 1. And a lighting control device 2 that controls the lighting fixture 3 based on the output from the lighting device 3.

照明器具３は、例えば蛍光ランプなどを光源（図示せず）と、光源の点灯電力を位相制御することで調光レベルを調整する調光回路（図示せず）とを備える。また照明器具３は、有線もしくは無線により照明制御装置２から送信される調光信号を受信可能としており、受信した照明制御装置２からの調光信号に基づいて、点灯、消灯、及び、調光レベルの調整などを行う。   The lighting fixture 3 includes, for example, a fluorescent lamp or the like as a light source (not shown) and a dimming circuit (not shown) that adjusts the dimming level by phase-controlling the lighting power of the light source. The lighting fixture 3 can receive a dimming signal transmitted from the lighting control device 2 by wire or wirelessly, and is turned on / off and dimmed based on the received dimming signal from the lighting control device 2. Adjust the level.

照明制御装置２は、図１に示すように、カメラ１からの出力に基づいて照明器具３の調光レベルを調整するための照明制御部２１と、照明領域の快適な明るさを示す明るさ目標値を記憶する記憶部とを備える。また照明制御装置２は、例えば、リモコン送信機能付きの照度計（図示せず）から送信される無線信号を受信して、無線信号に含まれる照度を照明制御部２１に出力する受信部２３とを備える。なお、リモコン送信機能付きの照度計及び、照度計と受信部２３との間で行われる無線通信については、既知の技術であるので説明を省略する。   As shown in FIG. 1, the lighting control device 2 includes a lighting control unit 21 for adjusting the dimming level of the lighting fixture 3 based on the output from the camera 1, and a brightness indicating a comfortable brightness of the lighting area. A storage unit for storing the target value. The illumination control device 2 receives a radio signal transmitted from an illuminometer (not shown) with a remote control transmission function, for example, and outputs the illuminance included in the radio signal to the illumination control unit 21. Is provided. Note that the illuminance meter with the remote control transmission function and the wireless communication performed between the illuminance meter and the receiving unit 23 are known techniques, and thus description thereof is omitted.

記憶部２２は、例えばＥＥＰＲＯＭ（Electical Erasable Programable ROM）などの不揮発性メモリであり、明るさ目標値として画素値αが記憶される。この画素値αは、後述する初期設定時において、カメラ１から出力される映像信号から求めた平均画素値であり、照明制御部２１によって記憶される。   The storage unit 22 is a non-volatile memory such as an EEPROM (Electric Erasable Programmable ROM), and stores a pixel value α as a brightness target value. This pixel value α is an average pixel value obtained from a video signal output from the camera 1 at the time of initial setting described later, and is stored by the illumination control unit 21.

照明制御部２１は、カメラ１から入力される映像信号の平均画素値を求め、この平均画素値を明るさ指標値とし、記憶部２２に記憶された画素値αと比較して、照明器具３の調光レベルを調整する調光信号を照明器具３に出力する。より具体的には、照明制御部２１は、映像信号から求めた平均画素値が記憶部２２に記憶された画素値αよりも高い場合には、照明器具３の調光レベルを下げる調光信号を照明器具３に送信する。また上記の平均画素値が記憶部２２に記憶された画素値αよりも低い場合には、照明器具３の調光レベルを上げる調光信号を照明器具３に送信する。照明制御部２１は、上記の平均画素値と画素値αとの差が所定の許容範囲内に納まるまで、上述の動作を繰り返し行うことで、照明領域の明るさを所望の範囲に保つ。   The illumination control unit 21 obtains an average pixel value of the video signal input from the camera 1, uses the average pixel value as a brightness index value, and compares the average pixel value with the pixel value α stored in the storage unit 22. A dimming signal for adjusting the dimming level is output to the luminaire 3. More specifically, when the average pixel value obtained from the video signal is higher than the pixel value α stored in the storage unit 22, the lighting control unit 21 reduces the dimming level of the lighting fixture 3. Is transmitted to the luminaire 3. When the average pixel value is lower than the pixel value α stored in the storage unit 22, a dimming signal for increasing the dimming level of the lighting fixture 3 is transmitted to the lighting fixture 3. The illumination control unit 21 keeps the brightness of the illumination area within a desired range by repeatedly performing the above-described operation until the difference between the average pixel value and the pixel value α falls within a predetermined allowable range.

カメラ１は、カメラ１を総合的に制御する制御部１５と、例えばＣＭＯＳセンサなどの撮像素子１１とを備え、撮像素子１１の検知範囲が図２に示す撮像領域となるように設置されておいる。所定の周期ごとに撮像領域を撮像して撮像素子１から出力される映像信号は、カメラ１が備えるγ特性補正部１２及び感度補正部１３により補正され、照明制御装置２に出力される。   The camera 1 includes a control unit 15 that comprehensively controls the camera 1 and an image sensor 11 such as a CMOS sensor. The camera 1 is installed such that the detection range of the image sensor 11 is the image area shown in FIG. Yes. The video signal output from the imaging device 1 by imaging the imaging area at predetermined intervals is corrected by the γ characteristic correction unit 12 and the sensitivity correction unit 13 included in the camera 1 and output to the illumination control device 2.

ここで、撮像素子１１に入射される光は、照明器具３により照明される被照射面で反射した光であるので、撮像素子１１から出力する映像信号は、照明領域が同じ明るさでの場合であっても被照射面となる床面の反射率によって異なる。すなわち、被照射面である床面の反射率が大きければ映像信号の出力は大きく、また、床面の反射率が小さければ映像信号の出力は小さくなる。   Here, since the light incident on the image pickup device 11 is light reflected by the irradiated surface illuminated by the lighting fixture 3, the video signal output from the image pickup device 11 has the same illumination area. Even so, it depends on the reflectance of the floor surface to be irradiated. That is, the output of the video signal is large if the reflectance of the floor surface, which is the irradiated surface, is large, and the output of the video signal is small if the reflectance of the floor surface is small.

γ特性補正部１２は、後述の制御部１５からの制御信号に含まれる基準γ特性値に基づいて動作し、撮像素子１１から入力される映像信号のγ特性を補正して、感度補正部１３に出力する。   The γ characteristic correction unit 12 operates based on a reference γ characteristic value included in a control signal from the control unit 15 to be described later, corrects the γ characteristic of the video signal input from the image sensor 11, and the sensitivity correction unit 13. Output to.

感度補正部１３は、後述の制御部１５からの制御信号に含まれる基準感度値に基づいて動作し、γ特性補正部１２から入力されるγ特性補正後の映像信号を所定の倍率で増幅することで、映像信号の感度を補正して後述の露光時間補正部１５に出力する。   The sensitivity correction unit 13 operates based on a reference sensitivity value included in a control signal from the control unit 15 to be described later, and amplifies the video signal after γ characteristic correction input from the γ characteristic correction unit 12 at a predetermined magnification. Thus, the sensitivity of the video signal is corrected and output to the exposure time correction unit 15 described later.

またカメラ１は、制御部１５からの制御信号に含まれる基準露光値に基づいて動作する露光時間補正部１４を備え、例えば、撮像素子１１に設けられたアイリス（図示せず）をモータ等で開閉駆動することで、適正露出となるように制御を行っている。より具体的には、感度補正部１３から入力される撮像信号から、垂直同期期間ごとに画像の明るさを示す測光値を検出し、この測光値が制御信号に含まれる基準値となるように、アイリスを開閉駆動している。   In addition, the camera 1 includes an exposure time correction unit 14 that operates based on a reference exposure value included in a control signal from the control unit 15. For example, an iris (not shown) provided in the image sensor 11 is moved by a motor or the like. Control is performed so that proper exposure is obtained by opening and closing. More specifically, a photometric value indicating the brightness of the image is detected for each vertical synchronization period from the imaging signal input from the sensitivity correction unit 13 so that the photometric value becomes a reference value included in the control signal. The iris is opened and closed.

またカメラ１は、例えばＥＥＰＲＯＭなどの不揮発性メモリからなる記憶部１６を備え、記憶部１６には制御部１５により上述の制御信号を生成するのに必要な基準γ特性値、基準感度値、及び、基準露光値が記憶されている。   In addition, the camera 1 includes a storage unit 16 composed of a nonvolatile memory such as an EEPROM, for example, and the storage unit 16 has a reference γ characteristic value, a reference sensitivity value, and the like necessary for generating the control signal by the control unit 15. The reference exposure value is stored.

制御部１５は、後述する初期設定において、露光時間補正部１４からの映像信号に基づいて、基準γ特性値、基準感度値、及び、基準露光値をそれぞれ求め、記憶部１６に記憶させる。また制御部１５は、初期設定が行われると、記憶部１６から各基準値（基準γ特性値、基準感度値、及び、基準露光値）を読み出して、γ特性補正部１２、感度補正部１３、及び、露光時間補正部１４に対応する基準値を含めた制御信号を送信する。   The control unit 15 obtains a reference γ characteristic value, a reference sensitivity value, and a reference exposure value based on the video signal from the exposure time correction unit 14 and stores the reference γ characteristic value, the reference exposure value, and the storage unit 16 in an initial setting described later. Further, when the initial setting is performed, the control unit 15 reads each reference value (reference γ characteristic value, reference sensitivity value, and reference exposure value) from the storage unit 16, and the γ characteristic correction unit 12 and the sensitivity correction unit 13. , And a control signal including a reference value corresponding to the exposure time correction unit 14 is transmitted.

ここで、上述の照明システムにおける初期設定について説明を行う。なお、図３及び図５における床面ＦＬ１〜ＦＬ３の反射率は、床面ＦＬ１の反射率が最も高く、床面ＦＬ２、ＦＬ３となるに従って床面の反射率は低くなっている。すなわち、照明領域の明るさが同じ場合には、床面ＦＬ１における撮像素子１１に入射する光量は、他の床面ＦＬ２、ＦＬ３における撮像素子１１に入射する光量よりも多くなる。   Here, the initial setting in the above-described illumination system will be described. 3 and 5, the floor surface FL1 to FL3 has the highest reflectance of the floor surface FL1, and the floor surface has a lower reflectance as it becomes the floor surfaces FL2 and FL3. That is, when the brightness of the illumination area is the same, the amount of light incident on the image sensor 11 on the floor surface FL1 is larger than the amount of light incident on the image sensor 11 on the other floor surfaces FL2 and FL3.

まず、照明領域に外光が入射しない環境で、照明領域の明るさが所望する快適な明るさとなるように照明器具３の調光レベルを調整する。ここで、γ特性補正部１２の基準γ特性値が０．５に、また感度補正部１３の基準感度値が、増幅率が１となる感度値に、それぞれ設定されているとすると、各床面ＦＬ１〜ＦＬ３のカメラ１からの出力は、図３に示すグラフのようになる。図３のグラフは、横軸を照明領域の明るさとし、縦軸をカメラ１から出力された映像信号の平均画素値としたグラフであり、照明領域が快適な明るさである場合の平均画素値をそれぞれＰ１〜Ｐ３としている。すなわち、照明領域の明るさが同じ快適な明るさであっても、カメラ１から出力される映像信号の平均画素値Ｐ１〜Ｐ３は、各床面ＦＬ１〜ＦＬ３の反射率の違いによって、それぞれ異なることとなる。   First, the dimming level of the luminaire 3 is adjusted so that the brightness of the illumination area becomes a desired comfortable brightness in an environment where external light does not enter the illumination area. Here, if the reference γ characteristic value of the γ characteristic correction unit 12 is set to 0.5, and the reference sensitivity value of the sensitivity correction unit 13 is set to a sensitivity value at which the amplification factor is 1, each floor is set. The outputs from the camera 1 on the surfaces FL1 to FL3 are as shown in the graph of FIG. The graph of FIG. 3 is a graph in which the horizontal axis is the brightness of the illumination area and the vertical axis is the average pixel value of the video signal output from the camera 1, and the average pixel value when the illumination area has a comfortable brightness. Are P1 to P3, respectively. That is, even if the brightness of the illumination area is the same comfortable brightness, the average pixel values P1 to P3 of the video signal output from the camera 1 are different depending on the reflectance of the floor surfaces FL1 to FL3. It will be.

ここで、カメラ１の制御部１５は、照明領域の明るさと映像信号から求まる平均画素値とが正比例の関係となり、且つ、この快適な明るさに設定された状態の平均画素値が目標値αとなるように基準γ特性値及び基準感度値を求めて、記憶部１６に記憶させる。   Here, the control unit 15 of the camera 1 has a direct proportional relationship between the brightness of the illumination area and the average pixel value obtained from the video signal, and the average pixel value in a state where the comfortable brightness is set is the target value α. The reference γ characteristic value and the reference sensitivity value are obtained so as to be stored in the storage unit 16.

ここでは、γ特性補正部に設定する基準γ特性値を１に固定し、平均画素値が目標値αとなるように基準感度値を変化させていくことで、基準γ特性値及び基準感度値を求める方法について説明する。   Here, the reference γ characteristic value and the reference sensitivity value are set by fixing the reference γ characteristic value set in the γ characteristic correction unit to 1 and changing the reference sensitivity value so that the average pixel value becomes the target value α. A method for obtaining the value will be described.

γ特性補正部１２においてγ特性値を１とする方法としては、例えば、γ特性値を調整可能な一般的なカメラを用いることができる。このようなカメラでは、カメラの撮像素子１１における各画素の解像度を8bitとすると、撮像素子１１からの入力は256段階で変化し、この256段階中の幾つかの段階でのγ特性のもつ傾き係数が設定可能である。この傾き係数を各段階で同じ値に設定し、その間は線形補完を行うことで、容易にγ特性値を１とすることができる。図４に示す例では、256段階中所定の6段階において傾き係数が設定可能であり、各段階における傾き係数（図４におけるβ１〜β６）を所定の値（図４におけるγ１）に設定して、その間は線形補完を行う。これにより、γ特性補正部１２から出力される映像信号のγ特性値を１に設定することができ、感度補正部１４などでγ特性を変化させなければ、カメラ１から出力される映像信号の照明領域の明るさに対する平均画素の関係は直線とすることができる。   As a method of setting the γ characteristic value to 1 in the γ characteristic correcting unit 12, for example, a general camera capable of adjusting the γ characteristic value can be used. In such a camera, when the resolution of each pixel in the image pickup device 11 of the camera is 8 bits, the input from the image pickup device 11 changes in 256 steps, and the slope of the γ characteristic at several steps in the 256 steps. A coefficient can be set. By setting the slope coefficient to the same value at each stage and performing linear interpolation during that time, the γ characteristic value can be easily set to 1. In the example shown in FIG. 4, the slope coefficient can be set in six predetermined stages out of 256 stages, and the slope coefficients in each stage (β1 to β6 in FIG. 4) are set to predetermined values (γ1 in FIG. 4). In the meantime, linear interpolation is performed. As a result, the γ characteristic value of the video signal output from the γ characteristic correction unit 12 can be set to 1. If the γ characteristic is not changed by the sensitivity correction unit 14 or the like, the video signal output from the camera 1 is not changed. The relationship of the average pixel to the brightness of the illumination area can be a straight line.

ここで、基準γ特性を１に固定すると、各床面ＦＬ１〜ＦＬ３の照明領域の明るさに対するカメラ１からの出力は、図５のグラフに示す関係となる。なお、図中のＰ１’〜Ｐ３’は、照明領域が快適な明るさである場合における、床面ＦＬ１〜ＦＬ３のカメラ１から出力される映像信号の平均画素値をそれぞれ示している。   Here, if the reference γ characteristic is fixed to 1, the output from the camera 1 with respect to the brightness of the illumination areas of the floor surfaces FL1 to FL3 has the relationship shown in the graph of FIG. Note that P1 'to P3' in the figure indicate the average pixel values of the video signals output from the camera 1 on the floors FL1 to FL3 when the illumination area has a comfortable brightness.

床面ＦＬ１を例に、基準感度値を求める方法について説明を行うと、映像信号の増幅率が１倍である感度値に設定された際の平均画素値Ｐ１’は画素値αよりも大いので（図６を参照）、感度補正部１３での増幅率が徐々に小さくなるよう基準感度値を変化させる。具体的には、まず制御部１５は、感度補正部１３における増幅率が１倍よりも小さな（例えば０．９倍）感度値を基準感度値として感度補正部１３に出力する。ここで、感度補正部１３が入力された制御信号に基づいて感度を補正すると、制御部１５で求めた平均画素値は、Ｐ１’よりも小さなＰ１’’となる。この平均画素値Ｐ１’’は、まだ画素値αよりも大きいので、制御部１５はさらに小さな増幅率（例えば０．８倍）となるよう制御信号を感度補正部１３に出力する。さらに感度補正部１３が入力された制御信号に基づいて感度を補正すると、制御部１５で求めた平均画素値は、画素値αと略等しくなるので、制御部１５は、この感度値（すなわち、増幅率が０．８倍となる感度値）を基準感度値として記憶部１６に記憶させる。   The method for obtaining the reference sensitivity value will be described using the floor surface FL1 as an example. The average pixel value P1 ′ when the gain value of the video signal is set to 1 is larger than the pixel value α. Therefore (see FIG. 6), the reference sensitivity value is changed so that the amplification factor in the sensitivity correction unit 13 gradually decreases. Specifically, first, the control unit 15 outputs a sensitivity value whose amplification factor in the sensitivity correction unit 13 is smaller than 1 (for example, 0.9 times) to the sensitivity correction unit 13 as a reference sensitivity value. Here, when the sensitivity correction unit 13 corrects the sensitivity based on the input control signal, the average pixel value obtained by the control unit 15 becomes P1 ″ smaller than P1 ′. Since the average pixel value P1 ″ is still larger than the pixel value α, the control unit 15 outputs a control signal to the sensitivity correction unit 13 so as to have a smaller amplification factor (for example, 0.8 times). When the sensitivity correction unit 13 further corrects the sensitivity based on the input control signal, the average pixel value obtained by the control unit 15 becomes substantially equal to the pixel value α. The sensitivity value at which the amplification factor is 0.8 times) is stored in the storage unit 16 as a reference sensitivity value.

この初期設定を、床面ＦＬ１〜ＦＬ３のそれぞれで行うことで、床面ＦＬ１〜ＦＬ３の反射率によらず、照明領域が快適な明るさである際にカメラ１出力される映像信号の平均画素は、画素値αとなる。また、カメラ１から出力される映像信号の平均画素値と照明領域の明るさの関係は正比例となる。   By performing this initial setting on each of the floor surfaces FL1 to FL3, regardless of the reflectance of the floor surfaces FL1 to FL3, the average pixel of the video signal output from the camera 1 when the illumination area has a comfortable brightness Is the pixel value α. The relationship between the average pixel value of the video signal output from the camera 1 and the brightness of the illumination area is directly proportional.

これにより、照明制御装置２において、照明器具３の調光レベルを制御する際の基準となる映像信号の平均画素値は、照明器具３の被照射面における反射率によらず所定の分解能を有する。さらに、被照射面における反射率によらず明るさ目標値となる画素値αを変化させる必要が無く、照明制御装置２は、単純な処理できめ細かな調光制御を行うことができる。   Thereby, in the lighting control apparatus 2, the average pixel value of the video signal which becomes a reference when controlling the light control level of the lighting fixture 3 has a predetermined resolution regardless of the reflectance on the irradiated surface of the lighting fixture 3. . Furthermore, it is not necessary to change the pixel value α that is the brightness target value regardless of the reflectance on the irradiated surface, and the illumination control device 2 can perform fine light control with simple processing.

ここで、明るさ目標値である画素値αは、例えば照明制御装置２に入力可能な画素値の上限に近い値（図６の画素値α２）に設定すると、外光が入射して照明領域が明るくなった際に、画素値の上限を超えてしまい、正常な調光制御が困難になる。また、画素値の上限から大きく離れた値（図６の画素値α１）に設定した場合には、照明制御装置２の調光制御における分解能が十分ではないため、きめ細かな調光制御を行うことが出来なくなる。   Here, when the pixel value α that is the brightness target value is set to a value close to the upper limit of the pixel value that can be input to the illumination control device 2, for example, the pixel value α2 in FIG. When becomes brighter, the upper limit of the pixel value is exceeded, and normal dimming control becomes difficult. In addition, when the value is set far from the upper limit of the pixel value (pixel value α1 in FIG. 6), the resolution in the dimming control of the illumination control device 2 is not sufficient, so fine dimming control is performed. Cannot be done.

本実施の形態においては、明るさ目標値となる画素値αは、照明制御装置２に入力可能な画素値の約５０％に設定されている。例えば、照明制御装置２における画素値の解像度を8bitとすると、画素値は0〜255の範囲であるので、画素値αを128に設定し、その前後10程度を許容範囲とする。   In the present embodiment, the pixel value α that is the brightness target value is set to about 50% of the pixel value that can be input to the illumination control device 2. For example, if the resolution of the pixel value in the illumination control device 2 is 8 bits, the pixel value is in the range of 0 to 255. Therefore, the pixel value α is set to 128, and about 10 before and after that is allowed.

このようにすることで、外光が入射して照明領域が明るくなっても照明制御装置２での上限を超えることがなく、照明制御装置２の調光制御において所定の分解能を保ち、きめ細かな調光制御を行うことができる。   By doing in this way, even if external light enters and the illumination area becomes bright, the upper limit of the illumination control device 2 is not exceeded, and a predetermined resolution is maintained and finely controlled in the dimming control of the illumination control device 2. Dimming control can be performed.

なお、γ特性値を調整可能な一般的なカメラにおいて、各段階の傾き係数をγ１よりも小さな値に設定することで、感度補正部１３における基準感度値を調整することなく、カメラ１からの出力を図６に直線で示したグラフのように設定することも可能である。すなわち、γ特性補正部１２が感度補正部１３を兼用して、照明領域の明るさと平均画素とが正比例の関係となり、且つ、快適な明るさである際の平均画素値を画素値αとなるよう撮像素子１からの映像信号を補正するようにしてもよい。   In a general camera capable of adjusting the γ characteristic value, by setting the slope coefficient of each step to a value smaller than γ1, the sensitivity from the camera 1 can be adjusted without adjusting the reference sensitivity value in the sensitivity correction unit 13. It is also possible to set the output as in the graph shown by a straight line in FIG. That is, the γ characteristic correction unit 12 also serves as the sensitivity correction unit 13 so that the brightness of the illumination area and the average pixel are in a directly proportional relationship, and the average pixel value when the brightness is comfortable is the pixel value α. The video signal from the image sensor 1 may be corrected as described above.

１ カメラ
１１ 撮像素子
１２ γ特性補正部
１３ 露光時間補正部
１４ 制御部
１５ 記憶部
１６ 感度補正部
２ 照明制御装置
２１ 照明制御部
２２ 記憶部
２３ 受信部
３ 照明器具 DESCRIPTION OF SYMBOLS 1 Camera 11 Image pick-up element 12 Gamma characteristic correction | amendment part 13 Exposure time correction | amendment part 14 Control part 15 Memory | storage part 16 Sensitivity correction | amendment part 2 Illumination control part 21 Illumination control part 22 Memory | storage part 23 Reception part 3 Lighting fixture

Claims (2)

照明器具と、
前記照明器具によって照明される被照射面を撮像して撮像信号を出力する撮像素子と、
前記撮像信号のγ特性を補正するγ特性補正手段と、
前記撮像信号の感度を補正する感度補正手段と、
前記γ特性及び感度の補正がされた映像信号に基づいて、前記照明器具による照明領域の明るさを示す明るさ指標を出力する明るさ指標生成手段と、
前記明るさ指標が所定の明るさ目標値に対して、所定の範囲内に収まるよう照明器具の調光レベルを制御する照明制御手段とを備え、
前記γ特性補正手段及び前記感度補正手段は、前記照明領域の明るさと前記明るさ指標とが正比例の関係となり、且つ、前記照明領域が所望の明るさである際に、前記明るさ指標が前記明るさ目標値となるよう前記撮像信号の補正を行うことを特徴とする照明システム。 Lighting equipment,
An imaging device that images an irradiated surface illuminated by the lighting fixture and outputs an imaging signal;
Γ characteristic correcting means for correcting the γ characteristic of the imaging signal;
Sensitivity correction means for correcting the sensitivity of the imaging signal;
Brightness index generating means for outputting a brightness index indicating the brightness of the illumination area by the luminaire based on the video signal in which the γ characteristic and sensitivity are corrected,
Illumination control means for controlling the dimming level of the luminaire so that the brightness index falls within a predetermined range with respect to a predetermined brightness target value;
The γ characteristic correcting unit and the sensitivity correcting unit have a direct proportional relationship between the brightness of the illumination area and the brightness index, and the brightness index is the desired brightness when the illumination area has a desired brightness. An illumination system, wherein the imaging signal is corrected so as to be a brightness target value. 前記明るさ目標値は、前記明るさ指標の最大値に対して、略５０％の値となるように設定されることを特徴とする請求項１に記載の照明システム。   The illumination system according to claim 1, wherein the brightness target value is set to be approximately 50% of a maximum value of the brightness index.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015069816A (en) * 2013-09-27 2015-04-13 株式会社メガチップス Lighting instrument identification device, illumination system and lighting instrument identification method
EP2827683A4 (en) * 2012-03-12 2015-09-23 Toshiba Kk Information processing device, image sensor device, and program
US20160088712A1 (en) * 2013-05-30 2016-03-24 Kmw, Inc. Device for controlling brightness of lighting device

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04316282A (en) * 1991-04-16 1992-11-06 Fuji Photo Film Co Ltd Picture memory device and its operation
JPH08129641A (en) * 1994-11-02 1996-05-21 Nippon Telegr & Teleph Corp <Ntt> Method and device for lightness adjustment based upon lightness perception characteristic
JPH10106757A (en) * 1996-09-27 1998-04-24 Mitsubishi Electric Corp Lighting system
JP2005276445A (en) * 2004-03-22 2005-10-06 Toshiba Lighting & Technology Corp Lighting control device and lighting system
JP2009224971A (en) * 2008-03-14 2009-10-01 Omron Corp Image processing device

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04316282A (en) * 1991-04-16 1992-11-06 Fuji Photo Film Co Ltd Picture memory device and its operation
JPH08129641A (en) * 1994-11-02 1996-05-21 Nippon Telegr & Teleph Corp <Ntt> Method and device for lightness adjustment based upon lightness perception characteristic
JPH10106757A (en) * 1996-09-27 1998-04-24 Mitsubishi Electric Corp Lighting system
JP2005276445A (en) * 2004-03-22 2005-10-06 Toshiba Lighting & Technology Corp Lighting control device and lighting system
JP2009224971A (en) * 2008-03-14 2009-10-01 Omron Corp Image processing device

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2827683A4 (en) * 2012-03-12 2015-09-23 Toshiba Kk Information processing device, image sensor device, and program
US20160088712A1 (en) * 2013-05-30 2016-03-24 Kmw, Inc. Device for controlling brightness of lighting device
EP3007520A4 (en) * 2013-05-30 2017-01-25 KMW Inc. Device for controlling brightness of lighting device
JP2015069816A (en) * 2013-09-27 2015-04-13 株式会社メガチップス Lighting instrument identification device, illumination system and lighting instrument identification method

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