JPH0656304B2 - Photoelectric encoder - Google Patents
Photoelectric encoderInfo
- Publication number
- JPH0656304B2 JPH0656304B2 JP1230906A JP23090689A JPH0656304B2 JP H0656304 B2 JPH0656304 B2 JP H0656304B2 JP 1230906 A JP1230906 A JP 1230906A JP 23090689 A JP23090689 A JP 23090689A JP H0656304 B2 JPH0656304 B2 JP H0656304B2
- Authority
- JP
- Japan
- Prior art keywords
- light
- light emitting
- grating
- emitting element
- photoelectric encoder
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
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- 229910021417 amorphous silicon Inorganic materials 0.000 description 6
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- 239000011521 glass Substances 0.000 description 3
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- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910001218 Gallium arsenide Inorganic materials 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 229910006404 SnO 2 Inorganic materials 0.000 description 1
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- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
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- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical group [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
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- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
- G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
- G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
- G01D5/36—Forming the light into pulses
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optical Transform (AREA)
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は光電型エンコーダ、特にスケールと光学系の改
良に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to improvements in photoelectric encoders, particularly scales and optical systems.
［従来の技術］ 各種測定器、工作機械、さらに最近は各種情報機械等に
も相対移動する二つの部材の変位量を検出するため各種
エンコーダが用いられており、非接触で変位量検出が可
能なところから光電型エンコーダが汎用されている。[Prior art] Various encoders are used to detect the amount of displacement of two members that move relative to each other, such as various measuring instruments, machine tools, and more recently, various information machines, and the amount of displacement can be detected without contact. Photoelectric encoders have been widely used for some reason.
該光電型エンコーダは相対移動する二つの部材のそれぞ
れに設けられた格子と、該格子の重なり合いを検出する
ための発光素子および受光素子より成る。The photoelectric encoder includes a grating provided on each of two members that move relative to each other, and a light emitting element and a light receiving element for detecting the overlapping of the gratings.
このような従来の光電型エンコーダとしては、通常の２
枚の格子の重なり合いを検出するエンコーダの他、第７
図に示すような３枚の格子の重なり合いの変化により変
位量を検出する、所謂３格子式（Journal of the potic
al society of America, 1965, vol,55, No,4, p373-38
1）、或いは第８図に示すような反射式の光電型エンコ
ーダ（特開昭５７−１９８８１４）等が周知である。As such a conventional photoelectric encoder, an ordinary encoder
In addition to the encoder that detects the overlap of the gratings,
The so-called three-lattice system (Journal of the potic
al society of America, 1965, vol, 55, No, 4, p373-38
1), or a reflection type photoelectric encoder as shown in FIG. 8 (Japanese Patent Laid-Open No. 57-198814) is well known.
第７図に示す３格子式エンコーダ１０は、平行配置され
た発光側格子１２、検出側格子１４と、両格子１２，１
４の間に相対移動可能に平行配置された基準格子１６
と、前記発光側格子１２の図中左側に配置された発光素
子１８と、前記検出側格子１４の図中右側に配置された
受光素子２０と、を含む。The three-grating encoder 10 shown in FIG. 7 includes a light-emitting side grating 12, a detection-side grating 14 and both gratings 12, 1 arranged in parallel.
Reference grid 16 arranged in parallel so as to be movable relative to each other
And a light receiving element 20 arranged on the left side of the light emitting side grating 12 in the drawing, and a light receiving element 20 arranged on the right side of the detection side grating 14 in the drawing.
そして、発光素子１８から出射された光は発光側格子１
２、基準格子１６、検出側格子１４を介して受光素子２
０に至り、該受光素子２０は各格子１２，１４，１６で
制限された照射光を光電変換し、さらにプリアンプ２２
により増幅して検出信号ｓを得る。Then, the light emitted from the light emitting element 18 is emitted from the light emitting side grating 1.
2, the light receiving element 2 through the reference grating 16 and the detection grating 14
0, the light receiving element 20 photoelectrically converts the irradiation light limited by the gratings 12, 14, 16 and further, the preamplifier 22
To obtain a detection signal s.
ここで、基準格子１６が発光側格子１２、検出側格子１
４に対し例えば矢印ｘ方向に相対移動すると、発光素子
１８からの照射光のうち格子１２，１６，１４により遮
蔽される光量が徐々に変化し、検出信号ｓは略正弦波と
して出力される。Here, the reference grating 16 is the light emitting side grating 12 and the detection side grating 1.
4, the amount of light shielded by the gratings 12, 16 and 14 in the irradiation light from the light emitting element 18 gradually changes, and the detection signal s is output as a substantially sine wave.
そして、前記基準格子１６のピッチＰ１と検出信号ｓの
波長が対応し、該検出信号ｓの波長およびその分割値よ
り前記基準格子１６の相対移動量を測定するものであ
る。The pitch P 1 of the reference grating 16 and the wavelength of the detection signal s correspond to each other, and the relative movement amount of the reference grating 16 is measured based on the wavelength of the detection signal s and its division value.
従って、基準格子１６をメインスケール２４に、発光側
格子１２，検出側格子１４をインデックススケール２６
にそれぞれ設置することにより、両スケールの相対移動
量を検出することができる。Therefore, the reference grating 16 is used as the main scale 24, and the light emitting side grating 12 and the detection side grating 14 are used as the index scale 26.
It is possible to detect the relative movement amount of both scales by installing the scales in each.
一方、第８図には反射式光電型エンコーダ１０が示され
ており、前記第７図と対応する部分には同一符号を付し
説明を省略する。On the other hand, FIG. 8 shows a reflective photoelectric encoder 10, and the portions corresponding to those in FIG. 7 are designated by the same reference numerals and the description thereof will be omitted.
図示例においてはメインスケール２４およびインデック
ススケール２６は光透過性のガラスより形成され、メイ
ンスケール２４には反射性の基準格子１６を形成し、イ
ンデックススケール２６には受光素子２０を格子状に形
成する。In the illustrated example, the main scale 24 and the index scale 26 are formed of light-transmissive glass, the main reference scale 16 is formed with a reflective reference grating 16, and the index scale 26 is formed with the light-receiving elements 20 in a lattice shape. .
従って、インデックススケール２６は、受光素子２０に
より前記第７図の発光側格子１２及び検出側格子１４に
対応するスリットが構成されることとなる。Therefore, in the index scale 26, the slits corresponding to the light emitting side grating 12 and the detecting side grating 14 of FIG.
そして、発光素子１８からの光は、コリメータレンズ２
８により平行光に調整され、インデックススケール２６
の裏面から照射される。Then, the light from the light emitting element 18 is emitted from the collimator lens 2
Adjusted to parallel light by 8, index scale 26
Is irradiated from the back side of the.
この結果、受光素子２０が形成されていない部分からの
み光が透過しメインスケール２４に照射される。As a result, the light is transmitted only from the portion where the light receiving element 20 is not formed, and the main scale 24 is irradiated with the light.
さらに、メインスケール２４上の基準格子１６に反射さ
れた光は再度インデックススケール２６方向へ進行し、
受光素子２０で光電変換される。Further, the light reflected by the reference grating 16 on the main scale 24 advances toward the index scale 26 again,
Photoelectric conversion is performed by the light receiving element 20.
ところが、基準格子１６の間隙に照射された光は、メイ
ンスケール２４がガラス製であるところから透過してし
まい、前記受光素子２０には至らない。However, the light applied to the gaps of the reference grating 16 is transmitted through the main scale 24 made of glass and does not reach the light receiving element 20.
以上のようにしてメインスケール２４とインデックスス
ケール２６の相対移動量は前記第７図の方式と同様に受
光素子２０に略正弦波として検出されることとなる。As described above, the relative movement amount of the main scale 24 and the index scale 26 is detected by the light receiving element 20 as a substantially sine wave, as in the system shown in FIG.
［発明が解決しようとする課題］ しかしながら、例えば第７図に示したような透過式の３
格子式光電型エンコーダによれば、スケール２４，２６
の両側に発光素子１８、受光素子２０を配置しなければ
ならず、部品点数が多く製造が煩雑であると共に、その
形状が大きくなってしまうという課題があった。[Problems to be Solved by the Invention] However, for example, the transmission type 3 as shown in FIG.
According to the lattice type photoelectric encoder, the scales 24, 26 are
Since the light emitting element 18 and the light receiving element 20 must be disposed on both sides of the above, there are problems that the number of parts is large and the manufacturing is complicated, and that the shape is large.
この点は第８図に示した反射式光電型エンコーダにおい
ても全く同様で、特に同図に示すような方式ではコリメ
ータレンズ２８を設けて光を分配しなければならず、や
はり装置の大型化は避けられないものであった。This point is exactly the same in the reflection type photoelectric encoder shown in FIG. 8. In particular, in the system shown in the figure, the collimator lens 28 must be provided to distribute the light, and the size of the device cannot be increased. It was inevitable.
本発明は前記従来技術の課題に鑑みなされたものであ
り、その目的は機構が簡単で、しかも小型軽量化を図る
ことのできる光電型エンコーダを提供することにある。The present invention has been made in view of the above problems of the prior art, and an object thereof is to provide a photoelectric encoder that has a simple mechanism and can be reduced in size and weight.
［課題を解決するための手段］ 前記目的を達成するために、本出願の請求項１記載の発
明にかかる光電型エンコーダは、その発光側格子基板を
板状発光素子より形成し、該板状発光素子の基準格子対
向面に遮光材を一定間隔で発光側格子の形状に配置した
ことを特徴とする。[Means for Solving the Problems] In order to achieve the above object, in a photoelectric encoder according to the invention of claim 1 of the present application, the light emitting side grating substrate is formed of a plate light emitting element, and the plate The light-emitting element is characterized in that light-shielding materials are arranged in the shape of the light-emitting side grid at regular intervals on the surface facing the reference grid.
また、本出願の請求項２記載の光電型エンコーダは、そ
の発光側格子基板が板状発光素子より形成され、該板状
発光素子の一面に受光素子を一定間隔で整列配置したこ
とを特徴とする。The photoelectric encoder according to claim 2 of the present application is characterized in that the light-emitting side grating substrate is formed of a plate-shaped light emitting element, and the light receiving elements are arranged at regular intervals on one surface of the plate-shaped light emitting element. To do.
［作用］ 本発明にかかる光電型エンコーダは前述した手段を有す
るので、発光側格子基板と発光素子が一体形成されるこ
ととなり、部品点数の削減、小型軽量化が図られること
となる。[Operation] Since the photoelectric encoder according to the present invention has the above-mentioned means, the light-emitting side grating substrate and the light-emitting element are integrally formed, so that the number of parts can be reduced and the size and weight can be reduced.
また、反射式光電型エンコーダにおいて、発光側格子基
板を構成する発光素子上に格子状受光素子を形成するこ
ととしたので、発光素子、受光素子、発光側格子、検出
側格子を全て一部材で構成することが可能となり、さら
に部品点数の削減、小型軽量化が図られることとなる。Further, in the reflective photoelectric encoder, since the grid-shaped light receiving element is formed on the light emitting element that constitutes the light emitting side grating substrate, the light emitting element, the light receiving element, the light emitting side grating, and the detection side grating are all made of one member. Therefore, the number of parts can be reduced, and the size and weight can be reduced.
［実施例］ 以下、図面に基づいて本発明の好適な実施例を説明す
る。尚、前記従来技術と対応する部分には符号１００を
加えて示し説明を省略する。[Embodiment] A preferred embodiment of the present invention will be described below with reference to the drawings. It should be noted that the reference numeral 100 is added to the portion corresponding to the above-mentioned prior art to omit the description.
第１図には本発明の一実施例にかかる光電型エンコーダ
に用いられる発光側格子基板の外観斜視図が示されてい
る。FIG. 1 is an external perspective view of a light emitting side grating substrate used in a photoelectric encoder according to an embodiment of the present invention.
同図に示す発光側格子基板１３０は、薄型長方形状に構
成され、極性の異なる半導体層１４０、１４２を積層配
置して両者間に発光用の接合面を形成している。The light-emission-side lattice substrate 130 shown in the figure is formed in a thin rectangular shape, and semiconductor layers 140 and 142 having different polarities are laminated and arranged to form a light-emission bonding surface between them.
本実施例においては、第１の半導体層１４０はＰ型Ｇａ
Ａｓ、第２の半導体層１４２はＮ型ＧａＡｓから成り、
主として近赤外光を発光する。In this embodiment, the first semiconductor layer 140 is made of P-type Ga.
As, the second semiconductor layer 142 is made of N-type GaAs,
It mainly emits near-infrared light.
そして、前記両半導体層１４０，１４２の端面には電極
用金属膜１４４，１４６が金の蒸着によって形成されて
いる。Then, metal films 144 and 146 for electrodes are formed on the end faces of the semiconductor layers 140 and 142 by vapor deposition of gold.
前記両電極用金属膜１４４，１４６にはそれぞれ高圧側
リード線１４８および低圧側リード線１５０がボンディ
ング接続されており、両電極を介して各半導体層１４
０，１４２に正孔および電子の注入が行なわれる。A high-voltage side lead wire 148 and a low-voltage side lead wire 150 are bonded and connected to the metal films 144 and 146 for both electrodes, respectively, and each semiconductor layer 14 is connected via both electrodes.
Holes and electrons are injected into 0 and 142.
従って、このように注入された正孔および電子は両半導
体層１４０，１４２の接続面において再結合し、この時
電子励起エネルギーによって所定の周波数の発光が行な
われるのである。Therefore, the holes and electrons thus injected are recombined at the connection surface between the two semiconductor layers 140 and 142, and at this time, electron excitation energy causes light emission at a predetermined frequency.
本発明において特徴的なことは、このような発光素子自
体が発光側格子基板となっていることであり、このため
本実施例においては前記発光が外部に出射する側の金属
膜１４４が格子を形成している。すなわち、本実施例に
おいては電極用金属膜１４４には一定間隔でスリット１
４４ａが複数設けられているのである。A feature of the present invention is that such a light emitting element itself serves as a light emitting side grating substrate. Therefore, in this embodiment, the metal film 144 on the side where the emitted light is emitted to the outside has a grating. Is forming. That is, in this embodiment, the slits 1 are formed on the electrode metal film 144 at regular intervals.
That is, a plurality of 44a are provided.
このスリットは、例えば２０μmピッチ、１０μmスリッ
トで構成されている。This slit is composed of, for example, a 20 μm pitch and a 10 μm slit.
従って、前記接合面からの発光は電極用金属膜１４４の
スリット１４４ａから外部に出射し、この光ビームの光
束形状は前記開口１４４ａのスリット形状によって定め
られることとなる。Therefore, the light emitted from the bonding surface is emitted to the outside from the slit 144a of the electrode metal film 144, and the luminous flux shape of this light beam is determined by the slit shape of the opening 144a.
尚、本実施例において反対側の電極用金属膜１４６は第
２の半導体層１４２の端面全部を覆い、また両半導体層
１４０，１４２の側面はその厚みが薄く、更に接合面と
は直交しているので発光がこれらの面から外部に漏洩す
る量は僅かであり、接合面での発光は効率的にスリット
１４４ａから出射することができる。無論、前記側面を
黒色塗料等で遮光することも好適である。In this embodiment, the electrode metal film 146 on the opposite side covers the entire end surface of the second semiconductor layer 142, and the side surfaces of both the semiconductor layers 140 and 142 are thin, and are perpendicular to the bonding surface. Therefore, the amount of emitted light leaking from these surfaces to the outside is small, and the emitted light at the joint surface can be efficiently emitted from the slit 144a. Of course, it is also preferable to shield the side surface with black paint or the like.
また、本発明において、両半導体層１４０，１４２はそ
の極性すなわちＰ型及びＮ型を逆転して配置することも
可能である。Further, in the present invention, both semiconductor layers 140 and 142 may be arranged so that their polarities, that is, P type and N type are reversed.
また、本実施例では近赤外光を発光することとしたが、
例えば半導体としてＧａＰあるいは（ＧａＡｌ）Ａｓ等
を用いることも好適であり、必要に応じて可視光の発光
を可能とする。Further, in the present embodiment, it was decided to emit near infrared light,
For example, it is also preferable to use GaP or (GaAl) As as a semiconductor, and it is possible to emit visible light as necessary.
また、電極用金属膜の形成には、前述した蒸着のほか、
スパッタリングその他任意の手法を用いることができ
る。In addition, in order to form the metal film for electrodes, in addition to the vapor deposition described above,
Any method such as sputtering can be used.
第２図には第１図に示した発光側格子基板１３０を光電
型リニアエンコーダに用いた状態が示されている。FIG. 2 shows a state in which the light emitting side grating substrate 130 shown in FIG. 1 is used in a photoelectric linear encoder.
即ち、被測定物の長さに応じて相対移動する基準格子１
１６と発光側格子１１２，検出側格子１４とで３格子シ
ステムを構成している。That is, the reference grating 1 that moves relative to the length of the object to be measured.
16 and the light emitting side grating 112 and the detecting side grating 14 constitute a three grating system.
そして、本実施例ではそれぞれがインデックススケール
よりなる４組の検出格子１１４ａ，１１４ｂ，…１１４
ｃを備えており、各検出格子に対応して受光素子１２０
ａ，１２０ｂ，…１２０ｃが配置されている。それぞれ
の検出格子１１４ａ，…１１４ｃは位相が互いに９０度
ずつずれたピッチの縦縞状目盛りが形成されている。従
って、各受光素子１２０ａ，…１２０ｃからはそれぞれ
π／２ずつ位相のずれたＡ相、Ｂ相、相、相の信号
を得ることができ、Ａ相−相により振幅増幅したＡ相
出力を、Ｂ相−相により同じく振幅増幅されたＢ相出
力を得る。該Ａ相出力およびＢ相出力の位相のずれ方向
等よりスケールの相対移動方向の弁別および電気的に検
出信号の分割を行ない、分解能の高い変位量検出を行な
っている。In this embodiment, four sets of detection grids 114a, 114b, ...
c is provided, and the light receiving element 120 is provided corresponding to each detection grating.
a, 120b, ... 120c are arranged. Each of the detection gratings 114a, ... 114c is formed with vertical stripe-shaped scales whose pitches are shifted by 90 degrees from each other. Therefore, it is possible to obtain A-phase, B-phase, phase, and phase signals each having a phase difference of π / 2 from each of the light-receiving elements 120a, ... The B-phase output, which is also amplitude-amplified by the B-phase, is obtained. Discrimination in the relative movement direction of the scale from the phase shift directions of the A-phase output and the B-phase output and the like, and the detection signal are electrically divided to detect the displacement amount with high resolution.
ここで、本実施例においては、前述したように発光側格
子基板１３０が発光素子より形成され、該発光素子に直
接発光側格子１１２が形成されているので、前記第７図
と比較しても明らかなように部品点数の削減および形状
の小型化が図られている。Here, in this embodiment, since the light emitting side grating substrate 130 is formed of the light emitting element and the light emitting side grating 112 is directly formed on the light emitting element as described above, even in comparison with FIG. As is apparent, the number of parts is reduced and the size is reduced.
第３図には本発明の第２実施例にかかる光電型エンコー
ダの概略構成図が示されており、前記第２図と対応する
部分には符号２００を加えて示し説明を省略する。FIG. 3 shows a schematic configuration diagram of a photoelectric encoder according to the second embodiment of the present invention, and a portion corresponding to that of FIG.
本実施例において特徴的なことは、発光側格子基板２３
０を発光素子から形成すると共に、検出側格子基板２３
２を受光素子と一体形成したことである。The characteristic of this embodiment is that the light emitting side grating substrate 23
0 is formed of a light emitting element, and the detection side grating substrate 23 is formed.
2 is integrally formed with the light receiving element.
即ち、本実施例にかかる検出側格子基板２３２は、第４
図に示すように構成されている。That is, the detection-side grating substrate 232 according to the present embodiment is the fourth
It is configured as shown in the figure.
第４図において、検出側格子基板２３２は、例えばガラ
スよりなる光透過性基材２５０上に光遮断性且つ導電性
材料、例えば金属膜より成る第１信号導出材層２５２
と、光を電気信号に変換するＰＮ半導体層２５４と、光
透過性且つ導電性材料例えばＩｎ２Ｏ３，ＳｎＯ２，Ｓ
ｉまたはこれらの混合物からなる第２信号導出材層２５
６と、をこの順序で積層形成した受光部２５８を細帯状
に一定ピッチで形成している。In FIG. 4, the detection-side grating substrate 232 has a first signal derivation material layer 252 made of a light-shielding and conductive material, for example, a metal film on a light-transmissive base material 250 made of, for example, glass.
A PN semiconductor layer 254 for converting light into an electric signal, and a light-transmissive and electrically conductive material such as In 2 O 3 , SnO 2 , S.
i or a second signal guiding material layer 25 made of a mixture thereof
6 and 6 are laminated in this order to form light receiving portions 258 in a strip shape at a constant pitch.
そして、検出側格子基板２３２は、その受光部２５８を
メインスケール２２４に対向して配置し、各受光部２５
８が第２図において受光素子１２０および検出側格子１
１４のスリットの役目を果すのである。In the detection-side grating substrate 232, the light receiving section 258 is arranged so as to face the main scale 224, and each light receiving section 25 is arranged.
In FIG. 2, reference numeral 8 denotes the light receiving element 120 and the detection side grating 1.
It plays the role of 14 slits.
なお、受光部２５８の第２信号導出材層２５６を通過し
た光はＰＮ半導体層２５４に至り、Ｎ型非晶質シリコン
膜２６０とＰ型非晶質シリコン膜２６２の境界面で光電
変換され、出力端子２６４，２６６から外部に取り出さ
れる。The light that has passed through the second signal guiding material layer 256 of the light receiving portion 258 reaches the PN semiconductor layer 254, and is photoelectrically converted at the boundary surface between the N-type amorphous silicon film 260 and the P-type amorphous silicon film 262. It is taken out from the output terminals 264 and 266.
以上説明したように、本発明の第２実施例にかかる光電
型エンコーダによれば、発光側格子基板を発光素子と一
体形成すると共に、検出側格子基板を受光素子と一体形
成することとしたので、更に部品点数の削減、小型軽量
化が図られることとなる。As described above, according to the photoelectric encoder according to the second embodiment of the present invention, the light emitting side grating substrate is integrally formed with the light emitting element, and the detection side grating substrate is integrally formed with the light receiving element. In addition, the number of parts can be reduced and the size and weight can be reduced.
第５図には本発明の第３実施例にかかる光電型エンコー
ダが示されており、前記第２実施例と対応する部分には
符号３００を加えて説明を省略する。FIG. 5 shows a photoelectric encoder according to the third embodiment of the present invention, and the portions corresponding to those in the second embodiment are designated by the reference numeral 300 and their explanations are omitted.
本実施例において特徴的なことは、反射式の光電型エン
コーダにおいて発光側格子基板、発光素子、検出側格子
基板、受光素子を一体形成したことにある。A feature of this embodiment is that the light emitting side grating substrate, the light emitting element, the detecting side grating substrate, and the light receiving element are integrally formed in the reflective photoelectric encoder.
即ち、第５図においてインデックススケール３７０は、
その基板が長尺状の発光素子３７２から構成され、その
一面に受光部３５８が形成されている。That is, the index scale 370 in FIG.
The substrate is composed of a long light emitting element 372, and a light receiving portion 358 is formed on one surface thereof.
従って、発光素子３７２から発した光は、メインスケー
ル３２４の基準格子３１６に反射され、受光部３５８に
至ることとなる。Therefore, the light emitted from the light emitting element 372 is reflected by the reference grating 316 of the main scale 324 and reaches the light receiving portion 358.
この際、発光素子３７２上に一定間隔で形成された受光
部３５８が発光側格子の役割を果し、更に受光部３５８
自体が格子状に形成されているため、検出側格子の役割
をも果すものである。At this time, the light receiving portions 358 formed on the light emitting element 372 at regular intervals serve as a light emitting side grating, and further, the light receiving portions 358.
Since it itself is formed in a grid shape, it also plays the role of a detection-side grid.
ここで、インデックススケール３７０の詳細な構成が第
６図に示されている。Here, the detailed structure of the index scale 370 is shown in FIG.
同図より明らかなように、発光素子３７２は、Ｐ型半導
体層３４０とＮ型半導体層３４２とから形成される。As is clear from the figure, the light emitting element 372 is formed of the P-type semiconductor layer 340 and the N-type semiconductor layer 342.
そして、該長尺状発光素子３７２上に一定間隔で受光部
３５８が形成される。Then, the light receiving portions 358 are formed on the elongated light emitting element 372 at regular intervals.
尚、各受光部３５８の構成は前記第４図に示した通りで
ある。The structure of each light receiving portion 358 is as shown in FIG.
次に、本実施例にかかるインデークススケール３７０の
製造方法について説明する。Next, a method of manufacturing the index scale 370 according to this embodiment will be described.
先ず、長尺状の発光素子３７２を常報により形成する。
そして、該発光素子３７２を真空蒸着装置内に装着し、
５×１０-6torrの真空度の環境下で、１５０〜２００℃
に加熱し、タングステンボードからＣｒを蒸着させ、発
光素子３７２上にＣｒを蒸着させて２０００〜３０００
Åの厚さの第１信号導出材層３５２となるＣｒ膜を形成
する。First, the elongated light emitting element 372 is formed by a conventional method.
Then, the light emitting element 372 is mounted in a vacuum vapor deposition device,
150 to 200 ° C under a vacuum of 5 × 10 -6 torr
2000 to 3000 by heating and then depositing Cr from the tungsten board and depositing Cr on the light emitting element 372.
A Cr film to be the first signal derivation material layer 352 having a thickness of Å is formed.
次に、前記Ｃｒ膜を形成した発行素子３７２をブラズマ
チャンバーに入れて３００℃に加熱し、ＳｉＨ４１０％
を含むＡｒガスをＨ２ガスにより１０倍希釈したガスを
前記プラズマチャンバー内に導入する。そして、０．１
〜２torrの圧力下で高周波グロー放電により、Ｎ型非晶
質シリコン（Ｎ−ａ−Ｓｉ）膜３６０およびＰ型非晶質
シリコン（Ｐ−ａ−Ｓｉ）膜３６２を、前記第１信号導
出材層３５２上に積層し、これによって約１μmの厚さ
の半導体層３５４を形成する。Next, the issuing element 372 having the Cr film formed thereon is put into a plasma chamber and heated to 300 ° C., and SiH 4 10%
A gas obtained by diluting Ar gas containing 10 times with H 2 gas is introduced into the plasma chamber. And 0.1
The N-type amorphous silicon (N-a-Si) film 360 and the P-type amorphous silicon (P-a-Si) film 362 are formed by the high-frequency glow discharge under a pressure of about 2 torr and the first signal deriving material. Stacked over layer 352, thereby forming a semiconductor layer 354 about 1 μm thick.
前記Ｎ型非晶質シリコン膜３６０は、析出初期に微量の
ＰＨ３を反応ガス中に混入することにより、またＰ型非
晶質シリコン膜３６２は途中で前記ＰＨ３をＢ２Ｈ６に
切換えることによりそれぞれ析出させる。ここで、ＰＮ
半導体層３５４の形成は、熱分解法、スパッタリグ蒸着
法等の他の方法によっても形成することが可能である。The N-type amorphous silicon film 360 is formed by mixing a very small amount of PH 3 into the reaction gas at the initial stage of deposition, and the P-type amorphous silicon film 362 switches the PH 3 to B 2 H 6 on the way. To cause precipitation. Where PN
The semiconductor layer 354 can be formed by another method such as a thermal decomposition method or a sputtering rig evaporation method.
次に、ＰＮ半導体層３５４を形成した発光素子３７２を
真空蒸着層内に入れ、１５０℃に加熱し、アルミナ壷に
入れたＩｎ２Ｏ３を電子ビーム蒸着法により約１０００
Åの厚さのＩｎ２Ｏ３膜として蒸着させ、これによって
前記ＰＮ半導体層３５４の上に第２信号導出材層３５６
を形成する。Next, the light emitting element 372 having the PN semiconductor layer 354 formed therein is placed in a vacuum deposition layer, heated to 150 ° C., and In 2 O 3 placed in an alumina pot is deposited by an electron beam deposition method to about 1000.
And a second signal lead layer 356 is deposited on the PN semiconductor layer 354 as an In 2 O 3 film having a thickness of Å.
To form.
次に、スピン塗装法によりホトレジストを約２μmの厚
さに塗布し乾燥させる。更にマスクにより出力端子部３
６６を遮光した後、紫外線で露光して現像し、出力端子
部３６６のホトレジストを除去する。Next, a photoresist is applied to a thickness of about 2 μm by a spin coating method and dried. Further, by using a mask, the output terminal portion 3
After shielding 66 from light, it is exposed to ultraviolet rays and developed to remove the photoresist of the output terminal portion 366.
ついで、ケミカルエッチングあるいはプラズマエッチン
グ等の方法により、出力端子３６６部分の第２信号導出
材層３５６およびＰＮ半導体層３５４を除去し、第１信
号導出材層３５２を露出させる。Then, the second signal lead-out material layer 356 and the PN semiconductor layer 354 in the output terminal 366 portion are removed by a method such as chemical etching or plasma etching to expose the first signal lead-out material layer 352.
同様にして、受光部３５８の間の光導出スリット３７４
部分以外の部分をホトレジストで覆い、該光導出スリッ
ト３７４に該当する第１，第２信号導出材層３５２，３
５６およびＰＮ半導体層３５４をプラズマエッチング等
により除去し、発光素子３７２を露出させる。Similarly, the light lead-out slit 374 between the light receiving portions 358 is formed.
A portion other than the portion is covered with photoresist, and the first and second signal derivation material layers 352 and 3 corresponding to the light derivation slit 374 are formed.
56 and the PN semiconductor layer 354 are removed by plasma etching or the like to expose the light emitting element 372.
尚、光導出スリット３７４の幅は受光部３５８の発光素
子３７２の表面からの高さの２倍以上とすると明暗を検
知するのに好適である。In addition, it is suitable to detect light and dark when the width of the light lead-out slit 374 is set to be twice or more the height of the light receiving portion 358 from the surface of the light emitting element 372.
次に、第１信号導出層３５２および第２信号導出層３５
６から出力電流を取出すための導線を前記出力端子３６
４，３６６に銅電線接着剤により取付け、最後にＰＮ半
導体層を保護するために全体に薄くシリコンワニスを塗
布乾燥して完成させる。Next, the first signal derivation layer 352 and the second signal derivation layer 35
The lead wire for taking the output current from the output terminal 36 is connected to the output terminal 36.
4, 366 is attached with a copper wire adhesive, and finally a thin silicon varnish is applied to the entire surface to protect the PN semiconductor layer and dried to complete.
以上のように、本実施例にかかる光電型エンコーダによ
れば、インデックススケールとメインスケールの二部材
のみで３格子システムの光電型エンコーダを構成するこ
とが可能となり、部品点数の大幅な削減、装置の小型軽
量化を図ることができる。As described above, according to the photoelectric encoder according to the present embodiment, it is possible to configure the photoelectric encoder of the three-grating system with only the two members of the index scale and the main scale, and it is possible to significantly reduce the number of parts and the device. It is possible to reduce the size and weight.
尚、前記各実施例によれば、３格子式光電型エンコーダ
を主体に説明したが、本発明は通常の２格子式光電型エ
ンコーダ等にも適用可能である。In addition, according to each of the above-described embodiments, the description has been made mainly on the three-lattice photoelectric photoelectric encoder, but the present invention is also applicable to a normal two-lattice photoelectric encoder and the like.
また、前記各実施例によれば、リニアエンコーダを例に
とり説明したが、これに限られるものではなく例えばロ
ータリーエンコーダ等にも適用可能である。Further, according to each of the above-described embodiments, the linear encoder has been described as an example, but the present invention is not limited to this and can be applied to, for example, a rotary encoder.
［発明の効果］ 以上説明したように、本出願の請求項１記載の光電型エ
ンコーダによれば、発光素子と発光側格子基板とを一体
形成したので、装置の小型軽量化、部品点数の削減を図
ることが可能となる。[Effects of the Invention] As described above, according to the photoelectric encoder according to claim 1 of the present application, since the light emitting element and the light emitting side grating substrate are integrally formed, the device is reduced in size and weight, and the number of parts is reduced. Can be achieved.
又、本出願の請求項２記載の光電型エンコーダによれ
ば、発光素子、発光側格子基板、受光素子、検出側格子
基板を一体形成することとしたので、更に部品点数の削
減、装置の小型軽量化を図ることが可能となる。Further, according to the photoelectric encoder of claim 2 of the present application, the light emitting element, the light emitting side grating substrate, the light receiving element, and the detecting side grating substrate are integrally formed, so that the number of parts can be further reduced and the apparatus can be downsized. It is possible to reduce the weight.
第１図は本発明の第一実施例に係る光電型エンコーダに
用いられる発光側格子基板の説明図、 第２図は第一実施例に係る光電型エンコーダの概略構成
図、 第３図は本発明の第二実施例に係る光電型エンコーダの
概略構成図、 第４図は第二実施例に用いられる検出側格子基板の説明
図、 第５図は本発明の第三実施例に係る光電型エンコーダの
説明図、 第６図は第三実施例に係る光電型エンコーダに用いられ
るインデックススケールの説明図、 第７図は従来の３格子式光電型エンコーダの概略構成
図、 第８図は従来の反射式光電型エンコーダの概略説明図で
ある。 １０，１１０，２１０，３１０……エンコーダ、 ２４，１２４，２２４……メインスケール、 ２６，１２６，２２６……インデックススケール、 １３０，２３０……発光側格子基板、 ２３２……受光側格子基板、 ３７０……インデックススケール。FIG. 1 is an explanatory diagram of a light emitting side grating substrate used in a photoelectric encoder according to the first embodiment of the present invention, FIG. 2 is a schematic configuration diagram of the photoelectric encoder according to the first embodiment, and FIG. FIG. 4 is a schematic configuration diagram of a photoelectric encoder according to a second embodiment of the invention, FIG. 4 is an explanatory diagram of a detection-side grating substrate used in the second embodiment, and FIG. 5 is a photoelectric type according to the third embodiment of the present invention. FIG. 6 is an explanatory diagram of an encoder, FIG. 6 is an explanatory diagram of an index scale used in the photoelectric encoder according to the third embodiment, FIG. 7 is a schematic configuration diagram of a conventional three-grating photoelectric photoelectric encoder, and FIG. It is a schematic explanatory drawing of a reflective photoelectric encoder. 10, 110, 210, 310 ... Encoder, 24, 124, 224 ... Main scale, 26, 126, 226 ... Index scale, 130, 230 ... Light emitting side grating substrate, 232 ... Receiving side grating substrate, 370 …… Index scale.
Claims (2)
ルと、 前記メインスケールに対し相対移動可能に並列配置さ
れ、所定の発光側格子が形成されたインデックススケー
ルと、 を含み、前記基準格子及び発光側格子により制限された
光を受光して前記メインスケールとインデックススケー
ルとの相対移動量を出力する光電型エンコーダにおい
て、 発光側格子基板を面発光する板状発光素子により形成
し、その基準格子対向面に薄膜状遮光材を一定間隔で前
記発光側格子の形状に配置したことを特徴とする光電型
エンコーダ。1. A main scale on which a predetermined reference grid is formed, and an index scale which is arranged in parallel so as to be movable relative to the main scale and on which a predetermined light-emission-side grid is formed. In a photoelectric encoder that receives light limited by the light emitting side grating and outputs the relative movement amount of the main scale and the index scale, the light emitting side grating substrate is formed by a plate light emitting element that emits surface light, and its reference grating A photoelectric encoder, wherein thin film light-shielding materials are arranged on the opposite surface at regular intervals in the shape of the light emitting side grating.
ルと、 前記メインスケールに対し相対移動可能に並列配置さ
れ、発光側格子及び検出側格子が形成されるインデック
ススケールと、 を含み、前記発光側格子を介した光が基準格子で反射さ
れ、更に検出側格子により制限された光を受光して、メ
インスケールとインデックススケールとの相対移動量を
出力する光電型エンコーダにおいて、 前記発光側格子基板を板状発光素子より形成し、該板状
発光素子の一面に一定間隔で受光素子を整列配置し、 前記発光素子より出射した光が受光素子間を介してメイ
ンスケールの基準格子により反射され、発光素子上の受
光素子により受光されることを特徴とする光電型エンコ
ーダ。2. A light emitting device comprising: a main scale on which a predetermined reference grating is formed; and an index scale which is arranged in parallel so as to be movable relative to the main scale and on which a light emitting side grating and a detection side grating are formed. In the photoelectric encoder, the light passing through the side grating is reflected by the reference grating, and the light limited by the detecting grating is received to output the relative movement amount between the main scale and the index scale. Is formed of a plate-shaped light emitting element, the light receiving elements are arranged in an array at a constant interval on one surface of the plate light emitting element, the light emitted from the light emitting element is reflected by the reference grid of the main scale through the light receiving elements, A photoelectric encoder characterized by being received by a light receiving element on a light emitting element.
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1230906A JPH0656304B2 (en) | 1989-09-05 | 1989-09-05 | Photoelectric encoder |
| PCT/JP1990/001138 WO1991003711A1 (en) | 1989-09-05 | 1990-09-05 | Photoelectric encoder |
| DE4091517A DE4091517C2 (en) | 1989-09-05 | 1990-09-05 | Photoelectric encoder with reference grid |
| DE19904091517 DE4091517T1 (en) | 1989-09-05 | 1990-09-05 | PHOTOELECTRIC CODING DEVICE |
| GB9109425A GB2243684B (en) | 1989-09-05 | 1991-05-01 | Photoelectric encoder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1230906A JPH0656304B2 (en) | 1989-09-05 | 1989-09-05 | Photoelectric encoder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0392716A JPH0392716A (en) | 1991-04-17 |
| JPH0656304B2 true JPH0656304B2 (en) | 1994-07-27 |
Family
ID=16915147
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1230906A Expired - Fee Related JPH0656304B2 (en) | 1989-09-05 | 1989-09-05 | Photoelectric encoder |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPH0656304B2 (en) |
| DE (1) | DE4091517C2 (en) |
| GB (1) | GB2243684B (en) |
| WO (1) | WO1991003711A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7132647B2 (en) | 2004-03-17 | 2006-11-07 | Canon Kabushiki Kaisha | Optical encoder |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6291839B1 (en) | 1998-09-11 | 2001-09-18 | Lulileds Lighting, U.S. Llc | Light emitting device having a finely-patterned reflective contact |
| DE19859670A1 (en) | 1998-12-23 | 2000-06-29 | Heidenhain Gmbh Dr Johannes | Readhead and method of making same |
| DE19917950A1 (en) | 1999-04-21 | 2000-10-26 | Heidenhain Gmbh Dr Johannes | Integrated optoelectronic thin film sensor, useful for scale scanning in a length, angle or two-dimensional measuring system, has a semiconductor layer of thickness corresponding to that of the detecting region of photodetectors |
| JP2002236034A (en) * | 2000-12-07 | 2002-08-23 | Harmonic Drive Syst Ind Co Ltd | Optical encoder |
| JP4880132B2 (en) * | 2001-05-11 | 2012-02-22 | 株式会社ミツトヨ | Photoelectric encoder |
| JP4498024B2 (en) | 2004-06-15 | 2010-07-07 | キヤノン株式会社 | Optical encoder |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4019196A (en) * | 1974-11-22 | 1977-04-19 | Stanley Electric Co., Ltd. | Indicating element and method of manufacturing same |
| JPS6032126B2 (en) * | 1981-06-01 | 1985-07-26 | 株式会社 三豊製作所 | Photoelectric encoder |
| GB2099993B (en) * | 1981-06-01 | 1985-11-27 | Mitutoyo Mfg Co Ltd | Photoelectric displacement encoder |
| JPS58147654A (en) * | 1982-02-26 | 1983-09-02 | Matsushita Electric Ind Co Ltd | optical frequency generator |
| JPS59221667A (en) * | 1983-05-31 | 1984-12-13 | Matsushita Electric Ind Co Ltd | Optical rotation detection device |
| JPS61283818A (en) * | 1985-06-10 | 1986-12-13 | Sharp Corp | Photoelectric type rotary encoder |
| JPS6324126A (en) * | 1986-06-25 | 1988-02-01 | Mitsutoyo Corp | Photoelectric encoder |
| US4943716A (en) * | 1988-01-22 | 1990-07-24 | Mitutoyo Corporation | Diffraction-type optical encoder with improved detection signal insensitivity to optical grating gap variations |
| JPH06324126A (en) * | 1993-05-10 | 1994-11-25 | Fujisaki Densetsu Kk | Protective relay testing device |
-
1989
- 1989-09-05 JP JP1230906A patent/JPH0656304B2/en not_active Expired - Fee Related
-
1990
- 1990-09-05 DE DE4091517A patent/DE4091517C2/en not_active Expired - Lifetime
- 1990-09-05 WO PCT/JP1990/001138 patent/WO1991003711A1/en active Application Filing
-
1991
- 1991-05-01 GB GB9109425A patent/GB2243684B/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7132647B2 (en) | 2004-03-17 | 2006-11-07 | Canon Kabushiki Kaisha | Optical encoder |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2243684A (en) | 1991-11-06 |
| WO1991003711A1 (en) | 1991-03-21 |
| DE4091517C2 (en) | 1997-04-30 |
| GB9109425D0 (en) | 1991-06-26 |
| GB2243684B (en) | 1993-07-07 |
| JPH0392716A (en) | 1991-04-17 |
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