JPS5963517A - Photoelectric encoder - Google Patents

Photoelectric encoder

Info

Publication number
JPS5963517A
JPS5963517A JP17417382A JP17417382A JPS5963517A JP S5963517 A JPS5963517 A JP S5963517A JP 17417382 A JP17417382 A JP 17417382A JP 17417382 A JP17417382 A JP 17417382A JP S5963517 A JPS5963517 A JP S5963517A
Authority
JP
Japan
Prior art keywords
main scale
light
scale
luminous flux
index
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.)
Granted
Application number
JP17417382A
Other languages
Japanese (ja)
Other versions
JPH0237963B2 (en
Inventor
Fujio Kanetani
金谷 冨士夫
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nikon Corp
Original Assignee
Nikon Corp
Nippon Kogaku KK
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nikon Corp, Nippon Kogaku KK filed Critical Nikon Corp
Priority to JP17417382A priority Critical patent/JPS5963517A/en
Publication of JPS5963517A publication Critical patent/JPS5963517A/en
Publication of JPH0237963B2 publication Critical patent/JPH0237963B2/ja
Granted legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01DMEASURING 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
    • G01D5/00Mechanical 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
    • G01D5/26Mechanical 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
    • G01D5/32Mechanical 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
    • G01D5/34Mechanical 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
    • G01D5/347Mechanical 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 using displacement encoding scales

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optical Transform (AREA)

Abstract

PURPOSE:To reduce the loss of the quantity of light and stray light due to reflection, and to facilitate manufacture by composing a main scale of a light transmitting member which has V-shaped grooves at equal intervals perpendicularly to a measurement direction. CONSTITUTION:An index scale 3 is provided in opposition to the main scale 1; luminous flux from a light source 4 is collimated by a collimator lens 5 and reaches the main scale 1, and transmitted luminous flux reaches photodetecting elements 6a and 6b, which generate output signals. The main scale 1 has the V- shaped grooves at equal intervals perpendicularly to the lengthwise directions, and two slanting surfaces 1a and 1b slant at a specific angle theta to constitute a prism made of a transparent material with a vertical angle theta. When luminous flux is made incident at right angles, pieces of projected parallel luminous flux from the slanting surfaces of each groove are diffracted to the opposite directions at an equal angle to obtain light parts (11a, 11b, 11c-) of width P/2 and dark parts of width P/2 alternately at specific intervals P, forming a corresponding light/dark grading on the main scale.

Description

【発明の詳細な説明】 本発明は計−11装置に用いられる光m式エンコーダに
関する。
DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical m-type encoder used in a total-11 device.

副長、測角に用いられる光賀式エンコーダとして、リニ
アエンコーダ、ロータリーエンコーダが知られている。
Linear encoders and rotary encoders are known as Koga encoders used for sub-length and angle measurements.

これらは、一般に、被測定物としての移動体又は回転体
に取りつけられて一体的に動く主スケールとこの主スケ
ールに対向して所定位置に固定されるインデックススケ
を有している。そして、各スケールには光の透過部と遮
光部とが等間隔で交互に格子状に形成されており、両ス
ケールの相対的移動による透過光の光量変化から主スケ
ールの移動前すなわち、被測Iff物の変位量が検出さ
れる。
These devices generally include a main scale that is attached to a moving body or a rotating body as an object to be measured and moves together with the main scale, and an index scale that is fixed at a predetermined position opposite to the main scale. Each scale has light transmitting parts and light blocking parts alternately formed in a lattice shape at equal intervals, and from the change in the amount of transmitted light due to relative movement of both scales, the The amount of displacement of the If object is detected.

このような従来の光シ式1/コーダでは、各スケールと
に交互に存在する光透過部と遮光部とが不可欠であり、
このために両スケールへ供給される光源からの光束の半
分は主スケールにより常に遮光され有効に入り用さ1t
ていない。しかも主スケールで遮光される尼ンよ少なか
らず反射するため迷光となって測定に悪影響を及ぼし易
かった。また、従来のこの棟のスケールはガラス基板上
にフォトリゾグラフィ技術によってクロム等の薄膜を形
成することによって製作されているため、製造工程が複
雑で結果的に高価な装置とならざるを得なかった。
In such a conventional optical scale type 1/coder, it is essential to have a light transmitting part and a light blocking part which are alternately present in each scale.
For this reason, half of the luminous flux from the light source supplied to both scales is always blocked by the main scale and is effectively used.
Not yet. Moreover, since the light is reflected to a large extent by the light shielded by the main scale, it becomes stray light that tends to adversely affect measurements. In addition, the scale of this conventional building was manufactured by forming a thin film of chromium or other material on a glass substrate using photolithography technology, which resulted in a complicated manufacturing process and an expensive equipment. Ta.

本発明の目的、ま上述のごとき欠点を解決すべく、光量
損失が少なく、反射による迷光も少なくしかも簡単に製
造し得る光1!式エンコーダを提供することにある。
The purpose of the present invention is to solve the above-mentioned drawbacks by creating a light beam that has less light loss, less stray light due to reflection, and can be easily produced! The purpose of the present invention is to provide an expression encoder.

本発明は、主スケールとこれに対向するインデックスス
クール、該両スケールへ平行光束を供給する照明装置及
び該両スケールf透過する光束を受光するI′C′¥[
変換装置を有する光ζ式エンコーダにおいて、主スケー
ルを測定方向に対して垂直方向の■型溝を測定方向にそ
って等間隔に有する*、透過部材で構成したものである
The present invention provides a main scale, an index school facing the main scale, an illumination device that supplies a parallel light flux to both scales, and an I'C'[
In an optical ζ-type encoder having a conversion device, the main scale is made of a transmissive member having *-shaped grooves perpendicular to the measurement direction at equal intervals along the measurement direction.

以下本発明を・図面に基づいて説明する。J第1図は本
発0AICよる光電式エンコーダの概略構成図である。
The present invention will be explained below based on the drawings. FIG. 1 is a schematic diagram of a photoelectric encoder based on the 0AIC of the present invention.

主スケール(1)はその長手方向すなわち矢印(2)で
示す方向に移動可能であり1図示なき被測定物体にi反
り付けられるものである。主スケール(1)に対向して
インデックススケール(3)が設けられ、光源(4)か
らの光束はコリメータレンズ(5)により平行光束とな
って主スケール(1)に達する。主スケール(1)及び
インデックススケール(6)を透過する)を東は、受光
素子(6へ)(6b)罠達し、出力信号を生ずる0 主スケール(1)は第2図(〜の部分拡大斜視図に示す
ごとく、長手方向(2) K対して垂直方向に等間隔の
V型溝を有している4、すなわち、第2図(8)の部分
断面図に示すごとく、V型溝を形成する2つの斜面(1
a)(1b)はそれぞれ所定の角度θだけ傾斜しており
、このV型溝はピッチPの等しい間隔で形成されている
。主スケール(1)はガラス又はプラスチックス等の透
明材料からなり、V型溝を形成する各斜面(1h)(1
b)は月 主スケール(1)の反射側の而(1C)とによりそれぞ
れ実質的に頂角θのプリズムを構成している従つC1こ
の主スケール(1)に平「i光束を第3図のごとく垂直
に入射させると、射出する平行光束は各V型溝の斜面ご
とに互いに反対方向へ等しい角度だけ屈折される。3そ
の結果隣接するV型溝との間に形成された稜線上で、各
稜線を境界として相接する斜面にてそれぞれ屈折された
斜めの平rテ光束が交わる。全てのV型溝が等しい傾角
の斜面で構成されているため各平行光束が交わる位置は
、生スケールの稜線から全て等しい距離りにちり、しか
も等間隔であ乙。すなわち、主スケール(1)から距離
りの平面上でのこれらの射出光束の〃テ面の洋子は44
図の平面図に示すごとく、1陥P/2の電束存在1fl
l (明部)(11a、11b、11c、・=)が[、
P / 2の光東不存在部(暗1y(I)を介して一定
の間隔Pで並び、この平面とで従来の主スケールに相当
する明暗格子が形成されて2八る。従って、この平面上
にインデックススケールを配置すれば実質的に従来の)
を電式エンコーダと同様に機能させることができる。
The main scale (1) is movable in its longitudinal direction, that is, in the direction shown by the arrow (2), and is warped against an object to be measured (not shown). An index scale (3) is provided opposite the main scale (1), and the light beam from the light source (4) is turned into a parallel light beam by a collimator lens (5) and reaches the main scale (1). The main scale (1) passes through the main scale (1) and the index scale (6)) and reaches the trap (6b) to the photodetector (6), producing an output signal. As shown in the perspective view, the V-shaped grooves are equally spaced in the vertical direction with respect to the longitudinal direction (2). Two slopes (1
a) and (1b) are each inclined by a predetermined angle θ, and the V-shaped grooves are formed at equal intervals of pitch P. The main scale (1) is made of a transparent material such as glass or plastic, and each slope (1h) (1h) forms a V-shaped groove.
b) and C1 on the reflecting side of the moon main scale (1) each substantially constitute a prism with an apex angle of θ. When the beam is incident perpendicularly as shown in the figure, the emitted parallel light beam is refracted by the same angle in opposite directions on each slope of each V-shaped groove.3 As a result, on the ridge line formed between the adjacent V-shaped grooves At this point, the oblique parallel beams of light that are refracted at the slopes adjacent to each other with each ridge as a boundary intersect.Since all the V-shaped grooves are composed of slopes with the same angle of inclination, the positions where the parallel beams of light intersect are They are all at the same distance from the ridgeline of the raw scale, and at equal intervals.In other words, the angle of the surface of these emitted light beams on the plane at the distance from the main scale (1) is 44.
As shown in the plan view of the figure, electric flux existence 1fl of 1 fall P/2
l (bright part) (11a, 11b, 11c, .=) is [,
They are lined up at a constant interval P through the P/2 Koto absent area (dark 1y(I), and together with this plane, a light-dark lattice corresponding to the conventional main scale is formed.28 Therefore, this plane If you place an index scale on top, it is essentially a conventional)
can function in the same way as an electronic encoder.

主スケール(りとインデックススケール(3)との間隔
りは1.せスケール(1)に形成されるV型溝の形状と
ピッチP及び主スケールを構成する透明部材の屈折餐n
、でよって定められる。瀉5図に示すごとく、1m溝を
形成する斜面(1a)(1b)の傾斜角をθとすれば、
主スケール(1)tに竹 対して垂直に入射する平光光束は各斜面に対して角度θ
で入射することになる。そして各斜面で屈折された後角
度θ′でこの面を射出するとすれば、周知の関係式 %式% が成立する。また、第5図に示したごとく、各斜面(1
a)(Ib)の中心を通る光線(10a’)(10b/
)の交点(A)とV型溝の稜線(→との距離か主スケー
ル(1)とインデックススケール〈己)との間隔りであ
り。
The distance between the main scale and the index scale (3) is 1. The shape and pitch P of the V-shaped groove formed on the main scale (1) and the refractive index n of the transparent member constituting the main scale.
, is determined by . As shown in Figure 5, if the inclination angle of the slopes (1a) and (1b) forming the 1m groove is θ, then
The flat light beam incident on the main scale (1) t perpendicularly to the bamboo is at an angle θ with respect to each slope.
It will be incident at If it is assumed that the light is emitted from this surface at an angle θ' after being refracted at each slope, the well-known relational expression % formula % holds true. In addition, as shown in Figure 5, each slope (1
a) Ray (10a') (10b/
) is the distance between the intersection (A) and the ridgeline of the V-shaped groove (→), or the distance between the main scale (1) and the index scale (self).

・−÷(−±万一・・。θ) が成り立つ。従って、主スケール(1)とインデックス
スケール(3)との間隔Did:主スケール(1)の構
と与えられる。
・−÷(−±In case...θ) holds true. Therefore, the interval Did between the main scale (1) and the index scale (3) is given as the structure of the main scale (1).

上記の説明では、V型溝を形成する斜面は全て等しい傾
角を有するものとしたが、このような形状が最も望まし
い。隣接する斜面の傾角が異なりV型溝の形状が非対称
である場合には、第4図に示したごときインデックスス
ケール(3)を配置する平面上での光敞分布は望ましい
ものではなくなる。すなわち、光束存在部と不存在部と
の位1置関係は第4図のごとき状態にはなるが、光栄存
在部内での光は分布が不均一となってしまい、実質的な
明暗格子を形成することは難しいからである。
In the above description, it is assumed that all the slopes forming the V-shaped groove have the same inclination angle, but such a shape is most desirable. If the inclination angles of the adjacent slopes are different and the shape of the V-shaped groove is asymmetrical, the light beam distribution on the plane on which the index scale (3) is arranged as shown in FIG. 4 will not be desirable. In other words, although the positional relationship between the light flux presence part and the light flux absence part is as shown in Figure 4, the distribution of light within the light flux presence part becomes uneven, forming a substantial light-dark grid. This is because it is difficult to do so.

インデックススケール(ろ)としては、従来と同様に例
えば第6図の平面図に示すごとく、幅P/2の透明部(
ろ1a)(32a)(ろ3a)  が幅P/2の遮)Y
I: Bl(をはさんでピッチPで形成された第1イ/
デツクスと、このドに隣接する同じ(幅P/2の透明部
(ろIfi)(32b)(′z)1b)  カ幅P/2
の遮光部をはさんでピッチPで形成された第2インデツ
クスとを有し、第1と第2のインデックスがP/4だけ
ずれたものを用いることが埴ましい。図では簡単のため
に第1と第2インデツクスと3ピツチとして示したが、
この数が多いほど測定誤差を小さくできることはいうま
でもない。
For example, as shown in the plan view of FIG. 6, the index scale (ro) is a transparent part (
1a) (32a) (3a) is a block with a width of P/2)Y
I: 1st I/ formed with pitch P across Bl(
Dex and the same (transparent part (Ifi) of width P/2) (32b) ('z) 1b adjacent to this card width P/2
It is preferable to use one having a second index formed at a pitch P across the light shielding part, and the first and second indexes being shifted by P/4. In the figure, the first and second indexes and three pitches are shown for simplicity, but
It goes without saying that the larger the number, the smaller the measurement error can be.

第7図はモスケール(1)とインデックススケール(ろ
)及び受光素子(6a)との関係を示す概略断面図であ
る。、主スケール(1)へ入射する平行光束・10は前
述のごとく主スケール(1)で分割かつ屈折され距離り
の平面上で実質的な明暗格子を形成し、インデックスス
クール(3)の透明部に達する光線のみが受光素子(6
a)に達する。主スケ−/’ (1) 左図中の矢印方
向(2)でインデックススケール(3)及び平行光束−
+[)K対して移動すると、主スケール(1)を射出す
る光束も主スケール(1)と一体向に幡幼し、インデッ
クススケール(3)をA過して受光素子(6a)に達す
る光量が変化する。そして、この光量変化が受光素子(
6a)の出力信号の変化となり、この変化を検出するこ
とにより主スケール(1)の柊動量すなわち被測定物体
の変位量が求められる。
FIG. 7 is a schematic cross-sectional view showing the relationship between the moscale (1), the index scale (ro), and the light receiving element (6a). , the parallel light flux 10 incident on the main scale (1) is divided and refracted by the main scale (1) as described above, forming a substantial light-dark grid on the distance plane, and the transparent part of the index school (3) Only the light that reaches the photodetector (6
Reach a). Main scale /' (1) Index scale (3) and parallel light flux in the direction of the arrow (2) in the left figure
+[) When moving relative to K, the light flux emitted from the main scale (1) also flies in the same direction as the main scale (1), passes through the index scale (3) A, and reaches the light receiving element (6a). changes. This change in the amount of light is reflected by the light receiving element (
6a), and by detecting this change, the amount of displacement of the main scale (1), that is, the amount of displacement of the object to be measured can be determined.

受光装置としてはインデックススケール(3) (D第
1.第2インデツクスに対応して第1と第2の受光素子
(6a)(6b)を配置−3ることか望ましく、これに
より、主スクール(1)の変位方向を判別できるととも
に主スケール(1)のピンチよりも微小な変位を検出す
ることができることはいうまでもない。また、信号処理
系としては第1図に図示したごとく、プリアンプ(2]
)、波形整形回FM5.a、方向弁別回路(2)を設け
、数値表示装置−により所望の表示形式により測定値を
表示することができる。
As a light receiving device, it is preferable to arrange the first and second light receiving elements (6a) and (6b) corresponding to the index scale (3) (D 1st and 2nd index -3). Needless to say, it is possible to determine the direction of displacement of the main scale (1) and also to detect a displacement smaller than a pinch of the main scale (1).In addition, as a signal processing system, as shown in Fig. 1, a preamplifier ( 2]
), waveform shaping cycle FM5. a. A direction discrimination circuit (2) is provided, and a numerical display device can display measured values in a desired display format.

信号処理系は従来の光硫式エンコーダと同一のものをそ
ご〕まま用いるCとができ、例えば本願と同一出願人に
よる出願(特開昭57−29911号公報)に開示され
た装置を組合せることによってより優れたエンコーダを
達成することかできる。
C can use the same signal processing system as the conventional optical sulfur encoder, for example, by combining the device disclosed in the application (Japanese Patent Laid-Open No. 57-29911) by the same applicant as the present application. A better encoder can be achieved by

以上のごとく、本発明によれば、主スケールに入射する
光束は全て透過し、従来の主スケールのように光束の半
分を遮光することがなhので供給する光束を有効に利用
することができ、また迷光による悪影響も少なくなりS
N比の良いj言号を得ることができる。しかも、主スケ
ールの製造にあたっては主スケールをプラスチックスで
構成することとすれば、従来のようにフォトリゾグラフ
ィ技術の複雑な工程を要せず、グラスチックの成型技術
により簡単かつ安価に犬縦生産することかり能となり、
本発明は極めて有効である。
As described above, according to the present invention, all the luminous flux incident on the main scale is transmitted through the main scale, and half of the luminous flux is not blocked like in the conventional main scale, so that the supplied luminous flux can be used effectively. , and the negative effects of stray light are also reduced.
It is possible to obtain j-words with a good N ratio. Moreover, when manufacturing the main scale, if the main scale is made of plastic, it does not require the complicated process of photolithography technology as in the past, and can be easily and inexpensively made using glass molding technology. By producing it, it becomes Noh,
The present invention is extremely effective.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は本発明による光゛這式1/コーダの概略構成図
、第2図(A)及び(Blは本発明に2ける主スケール
の部分拡大斜視図及び部外断面図、第ろ図及び第4図は
七スケールを透過する)YS束の説明図、第5図1ま主
スケールの構造の説明図、第6図はインデックススケー
ルの平面図、第7図は主スケールとインデックススケー
ルとの作用の説明図である。 (主−4部分の符号の説明) 1 °゛°主スケール ろ・・・・・インデックススケール 4・・・・先 源 5 ・・・・コリメータレンズ 6a、6b・・・・・受光素子 出願人 百本光学工業株式会社 伐埋人  渡 辺 隆 男 740 才5図 76区 A77図
FIG. 1 is a schematic configuration diagram of an optical crawler type 1/coder according to the present invention, and FIGS. Figure 4 is an explanatory diagram of the YS bundle (which transmits through seven scales), Figure 5 is an explanatory diagram of the structure of the first main scale, Figure 6 is a plan view of the index scale, and Figure 7 is a diagram showing the main scale and index scale. FIG. (Explanation of the symbols of the main-4 part) 1 °゛° Main scale... Index scale 4... Source 5... Collimator lenses 6a, 6b... Light receiving element applicant Hyakubon Optical Industry Co., Ltd. Takashi Watanabe, 740 years old, 5 years old, 76th ward, A77th figure

Claims (1)

【特許請求の範囲】[Claims] 主スケールとこれに対向するインデックススケール、該
両スケールへ平行光束を供給する照明装置及び該両スケ
ールを透過する光束を受光する光電変換装置を有する光
電式エンコーダにおいて、前記主スケールを測定方向に
対して垂直方向のV型溝を測定方向にそって等間隔に有
する光透過部材で′!tS成り、たことを特徴とする光
゛逝式エンコーダ。
In a photoelectric encoder having a main scale, an index scale facing the main scale, an illumination device that supplies parallel light flux to both scales, and a photoelectric conversion device that receives the light flux transmitted through both scales, the main scale is aligned in the measurement direction. A light transmitting member having vertical V-shaped grooves at equal intervals along the measurement direction. An optical encoder characterized by tS.
JP17417382A 1982-10-04 1982-10-04 Photoelectric encoder Granted JPS5963517A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP17417382A JPS5963517A (en) 1982-10-04 1982-10-04 Photoelectric encoder

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP17417382A JPS5963517A (en) 1982-10-04 1982-10-04 Photoelectric encoder

Publications (2)

Publication Number Publication Date
JPS5963517A true JPS5963517A (en) 1984-04-11
JPH0237963B2 JPH0237963B2 (en) 1990-08-28

Family

ID=15973976

Family Applications (1)

Application Number Title Priority Date Filing Date
JP17417382A Granted JPS5963517A (en) 1982-10-04 1982-10-04 Photoelectric encoder

Country Status (1)

Country Link
JP (1) JPS5963517A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5124548A (en) * 1990-05-03 1992-06-23 Canon Kabushiki Kaisha Encoder for detecting relative displacement having first and second scales and a light receiving device
WO1998037383A1 (en) * 1997-02-21 1998-08-27 Fanuc Ltd Optical encoder
WO1998059218A1 (en) * 1997-06-23 1998-12-30 Fanuc Ltd Optical rotary encoder
EP0928954A2 (en) * 1998-01-07 1999-07-14 Fanuc Ltd Optical encoder
FR2779815A1 (en) * 1998-06-02 1999-12-17 Ching Shun Wang Non-interference rotary encoder
WO2001035059A1 (en) * 1999-11-08 2001-05-17 Ballado Investments, Inc. Device for the optical detection and measurement of linear movements

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BRPI0811658A2 (en) * 2007-06-19 2015-02-10 3M Innovative Properties Co "SYSTEMS AND METHODS FOR IDENTIFYING A BLANK POSITION"

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS494551A (en) * 1972-03-15 1974-01-16
JPS5174659A (en) * 1974-12-24 1976-06-28 Nippon Electric Co

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS494551A (en) * 1972-03-15 1974-01-16
JPS5174659A (en) * 1974-12-24 1976-06-28 Nippon Electric Co

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5124548A (en) * 1990-05-03 1992-06-23 Canon Kabushiki Kaisha Encoder for detecting relative displacement having first and second scales and a light receiving device
WO1998037383A1 (en) * 1997-02-21 1998-08-27 Fanuc Ltd Optical encoder
US6703601B2 (en) 1997-02-21 2004-03-09 Fanuc, Ltd. Motion detection of an optical encoder by converging emitted light beams
WO1998059218A1 (en) * 1997-06-23 1998-12-30 Fanuc Ltd Optical rotary encoder
EP0928954A2 (en) * 1998-01-07 1999-07-14 Fanuc Ltd Optical encoder
EP0928954A3 (en) * 1998-01-07 2001-09-19 Fanuc Ltd Optical encoder
FR2779815A1 (en) * 1998-06-02 1999-12-17 Ching Shun Wang Non-interference rotary encoder
WO2001035059A1 (en) * 1999-11-08 2001-05-17 Ballado Investments, Inc. Device for the optical detection and measurement of linear movements

Also Published As

Publication number Publication date
JPH0237963B2 (en) 1990-08-28

Similar Documents

Publication Publication Date Title
US4974962A (en) Opto-electronic scale-reading apparatus
US4677293A (en) Photoelectric measuring system
US3344700A (en) Displacement measuring system
JPH06229781A (en) Displacement measuring equipment
JPS5963517A (en) Photoelectric encoder
US3285123A (en) Scale reading apparatus
WO2015190296A1 (en) Diffraction grating and displacement measurement device
JP2704017B2 (en) Optical encoder
JPS58135405A (en) Photoelectric displacement detector
JPS60190812A (en) Position detector
JPS61712A (en) Optical scale reader
JPH0627645B2 (en) Two-dimensional displacement detector
JP4343350B2 (en) Optical encoder
SU1434242A1 (en) Device for measuring film thickness
JPH0253728B2 (en)
JPH01121723A (en) Optical encoder
JPH09264712A (en) Movement detecting device
JPS6126005B2 (en)
JPS62298704A (en) Optical length measuring apparatus
JP3429961B2 (en) Optical encoder
JPH0399220A (en) Encoder
JPH05256670A (en) Rotary encoder and encoder
JPS642925B2 (en)
SU947642A1 (en) Phptoelectric pickup of object angular poition
JPH0961160A (en) Measuring apparatus for inclination amount of moving object