JPS6129718A - Photoelectric transmission type encoder - Google Patents
Photoelectric transmission type encoderInfo
- Publication number
- JPS6129718A JPS6129718A JP15106884A JP15106884A JPS6129718A JP S6129718 A JPS6129718 A JP S6129718A JP 15106884 A JP15106884 A JP 15106884A JP 15106884 A JP15106884 A JP 15106884A JP S6129718 A JPS6129718 A JP S6129718A
- Authority
- JP
- Japan
- Prior art keywords
- light
- transparent
- light transmission
- parts
- transparent body
- 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
Links
- 230000005540 biological transmission Effects 0.000 title claims abstract description 19
- 238000001514 detection method Methods 0.000 claims abstract description 4
- 239000011295 pitch Substances 0.000 abstract description 25
- 238000005259 measurement Methods 0.000 abstract 1
- 238000007796 conventional method Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
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
- G01D5/347—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 using displacement encoding scales
- G01D5/34707—Scales; Discs, e.g. fixation, fabrication, compensation
- G01D5/34715—Scale reading or illumination devices
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optical Transform (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用すｌ
−／７’ｌ 朶ｌＩ＋１１ ｔ＋ （Ｉｒｄ 斗＋
ｒ Ｔ ４＋Ｉ＝ １ｍ ｊｔｌ； ／ｎ開齢÷−フル
の回動角度の検出、あるいは往復動テーブルの直線移動
距離の検出等に利用される充電式透過型エンコーダに関
する。[Detailed description of the invention] Industrial use l −/7'l 朶lI+11 t+ (Ird 斗+
The present invention relates to a rechargeable transmission encoder used for detecting the rotation angle of r T 4 + I = 1 m jtl; /n opening age ÷ - full, or detecting the linear movement distance of a reciprocating table.
従来の技術
第２図は、直線移動距離の検出に利用されるものの従来
技術の原理を説明するためのものである。これは細巾の
板状体の、微小一定距離ごとにスリット状の透光部１１
，１１．・・・と非透光部１２，１２．・・・を等間隔
で同じ巾に交互に形成した第１の透光体１０と、上記と
同じように透光部２１，２１．・・・と非透光部２２，
２２．・・・が交互に形成された第２の透光体２０とを
間隔を有して重合状態にし、その第１．＄２の透光体１
０．２０を挟んで投光部１と受光部２を対向させたもの
であり、投光部１がら発光させた略平行光を第１の透光
体１０の透光部１．Ｌｌｌ、・・・を介して第２の透光
体２０に照射し、その照射光のうち透光部２１．２１．
・・・を通過した光を受光部２で受け、その受光量に対
応した電圧を発生させるようにしたものである。BACKGROUND OF THE INVENTION FIG. 2 is a diagram for explaining the principle of a conventional technique used to detect linear movement distance. This is a thin plate-like body with slit-shaped transparent parts 11 at every minute constant distance.
, 11. ... and non-transparent parts 12, 12 . . . , formed alternately with the same width at equal intervals, and the same transparent parts 21, 21 . . . as described above. ... and the non-transparent part 22,
22. . . are formed alternately with the second transparent bodies 20 at intervals, and the first . . . Transparent body 1 for $2
A light projecting section 1 and a light receiving section 2 are opposed to each other with a distance of 0.20 mm between them, and substantially parallel light emitted from the light projecting section 1 is transmitted to the light transmitting section 1.0 of the first light transmitting body 10. Lll, .
... is received by the light receiving section 2, and a voltage corresponding to the amount of received light is generated.
尚、通常は透光体１０．または２０のいずれか一方を静
止させ、他方を被検出対象と一体化させるが、両者を異
なる移動体に結合して相対移動量を検出することもあり
、その場合には、投・受光部１，２もいずれか一方と結
合することになる。以」二のものにおいては、透光体１
０と透光体２０とがそのピッチ（透光部１１，１１．・
・または２１．２１．・・・の配列間隔）分だけ相対移
動するごとに、透光部１１，１１．・・と透光部２１，
２］、・・・の重合面積が周期的に変化し、その結果、
透光部１から受光部２に達する光量が周期的に変わり、
受光部２からは周期的に変化する交番電圧信号が取り出
される。したがって、この交番電圧信号の周期数を測定
することにより透光体１０と透光体２０の相対移動量が
求められる。尚、」二記は直線移動距離の検出用のもの
であるが、回動角度の検出用は、透光体１０、透光体２
０のいずれが一方または両方を円板の周辺に形成する点
が異なるだけで、他は何等異なる点はない。Incidentally, normally the transparent body 10. Alternatively, either one of 20 is made stationary and the other is integrated with the object to be detected, but both may be coupled to different moving bodies to detect the relative movement amount. , 2 will also be combined with either one. In the second case, the transparent body 1
0 and the transparent body 20 have the same pitch (transparent parts 11, 11...
・Or 21.21. . . . each time the translucent portions 11, 11 . . . ... and the transparent part 21,
2], the polymerization area of... changes periodically, and as a result,
The amount of light reaching the light-receiving part 2 from the light-transmitting part 1 changes periodically,
A periodically changing alternating voltage signal is extracted from the light receiving section 2 . Therefore, by measuring the number of cycles of this alternating voltage signal, the amount of relative movement between the transparent body 10 and the transparent body 20 can be determined. Note that "2" is for detecting the linear movement distance, but for detecting the rotation angle, the transparent body 10 and the transparent body 2 are used to detect the rotation angle.
The only difference is that one or both of the 0's are formed around the disk, and there are no other differences.
ところで、この種のものの検出分解能は、透光部１１，
１１．・・・と透光部２１，２Ｌ・・・のピッチにより
決定されることになり、結局、高分解能のものを形成す
るには、それだけピッチを小さくしなければならず、製
作および価格のいずれの面でも制約がある。By the way, the detection resolution of this kind of thing is as follows:
11. ... and the pitch of the transparent parts 21, 2L..., and in the end, in order to form a high-resolution one, the pitch must be made that much smaller, which leads to problems in production and price. There are also restrictions in terms of
倉明が解決しようとする問題点
本発明は、高分解能の充電式透過型エンコーダを実現す
るに際してピッチの微小化を解決しようとするものであ
る。Problems to be Solved by Kuraaki The present invention attempts to solve the problem of miniaturization of the pitch when realizing a high-resolution rechargeable transmission encoder.
問題点を解決するための手段
本発明は、所定ピッチごとに透光部が形成された第１．
第２の透光体を挟んで投光部と受光部を配設し、第１．
第２の透光体の相対移動量を光電的に検出するようにし
た充電式透過型エンコーダにおいて、第２の透光体を挟
んで第１の透光体の反対側に第１の透光体と一体化した
第３の透光体を設け、第２の透光体の透光部はそのピッ
チの５０％より小とし、投光部の投光は散乱光にしたら
のである。Means for Solving the Problems The present invention provides a first...
A light projecting section and a light receiving section are arranged with a second transparent body in between, and the first.
In a rechargeable transmission type encoder that photoelectrically detects the amount of relative movement of a second transparent body, a first transparent body is placed on the opposite side of the first transparent body with the second transparent body in between. A third light transmitting body is provided which is integrated with the body, the light transmitting parts of the second light transmitting body are made smaller than 50% of the pitch, and the light emitted by the light projecting part is scattered light.
負りＷ
投光部からは散乱光がｆ５１の透光体上に放射され、そ
の透光部を通過した光が第２の透光体」二に放射され、
その透光部を通過し、続いて第３の透光体上に達し最後
にその透光部を通貨した光が受光部に導入される。した
がって、散乱光の入射角とｌ−第３の透光体の透光部を
結ぶ空間が大きいほど透過光景は大となり、その光路中
にいずれかの非透過部が位置した場合にはそこで遮光さ
れることになる。このようにして最終的に受光部に達す
る光量の大きさは、第１．第３の透光体の透光部と第２
の透光体の透光部との対向位置関係に応じて変わり、両
者の透光部の完全対向状態およびその配列ピッチの１７
２ずれた状態で最大、配列ピッチの１／４、および３／
４ずれた状態で最小となり、その最大、最小間は単調に
変化する。この結果、受光部には、第１．第３の透光体
と第２の透光体が相対的に１ピツチ移動するごとに２周
期の周期的変化を生ずる交番電圧が発生する。Negative W Scattered light is emitted from the light projecting part onto the transparent body f51, and the light that has passed through the transparent part is emitted to the second transparent body.
The light that passes through the light-transmitting portion, then reaches the third light-transmitting body, and finally passes through the light-transmitting portion is introduced into the light-receiving portion. Therefore, the larger the space connecting the incident angle of the scattered light and the transparent part of the third transparent body, the larger the transmitted scene becomes.If any non-transparent part is located in the optical path, the light will be blocked there. will be done. In this way, the amount of light that finally reaches the light receiving section is determined by the first. The transparent part of the third transparent body and the second
It varies depending on the facing positional relationship between the transparent body and the transparent part, and the completely facing state of both transparent parts and the arrangement pitch of 17
Maximum when shifted by 2, 1/4 of the array pitch, and 3/
It reaches a minimum when it is shifted by 4, and changes monotonically between the maximum and minimum. As a result, the light receiving section has the first. Every time the third light-transmitting body and the second light-transmitting body move relative to each other by one pitch, an alternating voltage that causes a periodic change of two periods is generated.
実施例
第１図は本発明の直線移動距離検出用のものについての
実施例であり、前記第２図と同番号を付した透光体１０
は、第２図と同様のものであり、同じ幅の透光部１１．
Ｉ Ｌ・・と非透光部１２が交互に形成されている。そ
の第１の透光体１０と対向して配設されたのが第２の透
光体２０′であり、反射部２１゜２１、・・・と非透光
部２２’ 、２２’ 、・・とが交互に形成され、その
透光部２１′、・・・の配列ピッチは前記透光体１０の
透光部１１、・・・のピッチと等しく、その巾は非透光
部２２・・の中より小となり、図では透光部２１′はピ
ッチの５０％より小さい例えば２５％に形成されている
。そのｆｉ′Ｓ２の透光体２０′の反対側の面と対向し
て配設されたのが第１の透光体１０と全く同一構造の＠
３の透光体３０であり、透光部３１と非透光部３２が等
間隔で交互に形成されている。そして、第１．第３の透
光体１０．３０の外側には散乱光を発光する投光部１′
と受光部２が配設され両者は対向している。Embodiment FIG. 1 is an embodiment of the present invention for detecting linear movement distance, and the transparent body 10 with the same number as in FIG.
are similar to those shown in FIG. 2, and have the same width as the transparent portion 11.
IL... and non-transparent parts 12 are formed alternately. A second transparent body 20' is arranged opposite to the first transparent body 10, and includes reflective parts 21, 21, . . . and non-transparent parts 22', 22', . The arrangement pitch of the transparent parts 21', . . . is equal to the pitch of the transparent parts 11, . In the figure, the transparent portion 21' is formed to have a pitch smaller than 50%, for example, 25%. The one disposed opposite the surface opposite to the light transmitting body 20' of fi'S2 has the same structure as the first light transmitting body 10.
3, in which transparent parts 31 and non-transparent parts 32 are alternately formed at equal intervals. And the first. On the outside of the third transparent body 10.30 is a light projecting section 1' that emits scattered light.
and a light-receiving section 2 are arranged, and both are facing each other.
以上のものにおいては、投光器１′から放射された散乱
光は第１の透光体１０に達し、そのうち透光部１１．ｌ
’ｌ、・・を通過した光が第２の透光体２０′上に放射
され、続いてその透光部２１’、２１’ ・・・を通
過した光が第３の透光体３０に放射され、最後にその透
光部３１，３１．・・・を通過した光が受光部２に達す
る。このとき、受光部２に達する光量は、第１．第３の
透光体１０．３０の透光部１１．．１１．・・・、３１
，３１．・・・と第２の透光体２０′の透光部２１’、
２１’ ・・・との対向位置関係に応じ変化する。In the above structure, the scattered light emitted from the projector 1' reaches the first transparent body 10, and among them, the transparent part 11. l
The light that has passed through 'l, . The light is emitted, and finally the transparent parts 31, 31 . The light that has passed through reaches the light receiving section 2. At this time, the amount of light reaching the light receiving section 2 is the first. Transparent portion 11 of third transparent body 10.30. ．． 11. ..., 31
, 31. ... and the transparent portion 21' of the second transparent body 20',
21'... changes depending on the opposing positional relationship.
第３〜６図は、上記の透光部１１，１１．・・３１．３
１．・・・と透光部２１’、２１’＋・・・どの対向位
置関係とそのときに一つの透光部１１を通過した光のう
ち何％が受光部２に達するかを投光点を横軸にモデル化
して示したものであり、ここには投光部１′と第１の透
光体１０問および受光部２と第３の透光部３０間、の各
間隔をそれぞれ透光部２１′。3 to 6 show the above-mentioned light-transmitting parts 11, 11.・31.3
1. . . . and the transparent parts 21', 21'+... The light emitting point is determined to determine which opposing positional relationship and what percentage of the light that passes through one transparent part 11 reaches the light receiving part 2. It is modeled and shown on the horizontal axis, and each interval between the light transmitting part 1' and the first transparent body 10 and between the light receiving part 2 and the third transparent part 30 is shown as a light transmitting body. Part 21'.
２１′、・・・（透光部１１．ＩＬ・・・）の配列ピッ
チと同じとし、第１．第２．第３の透光体１０．２０”
、３０の各間隔を１／２ピツチとしである。第３図の
状態は透光部１１゜１１、・・と透光部２１’、２１’
、・・・が１／２ピツチずれ、第４図は第３図の状態か
ら透光体２０′が１／４ピツチ分左方にずれ、第５図は
第３図の状態から透光体２０′が左方に１／２ピツチず
れて透光部１１，１ ］、・・・と透光部２１″が完全
に対向し、第６図は第３図の状態から透光体２０′が左
方に３／４ピツチずれた状態を示している。そして矢印
付の線により囲まれた面積は投光体１′のある１点から
の散乱光のうち透光体１０の中央部の−っの透光部ｊ１
を通過する光線を示し、その中のハツチング部分は第２
．第３の透光部２１’、３］を通過する光量を示し、各
図の下側は、上記透光部１１を通過する全光量に対し、
受光部２に達した光量の割合を百分率で示したものであ
る。21', . . . (transparent portions 11.IL . Second. Third transparent body 10.20”
, 30, each interval is 1/2 pitch. In the state shown in Fig. 3, the transparent parts 11°11, . . . and the transparent parts 21', 21'
, . 20' is shifted by 1/2 pitch to the left so that the transparent parts 11,1], . . . and the transparent parts 21'' completely oppose each other, and FIG. is shifted by 3/4 pitch to the left.The area surrounded by the arrowed line is the area in which the central part of the light transmitting body 10 out of the scattered light from a certain point of the light projecting body 1' is shown. -translucent part j1
The hatched part is the second
．． The amount of light passing through the third transparent section 21', 3] is shown, and the lower part of each figure shows the amount of light passing through the third transparent section 11,
The ratio of the amount of light reaching the light receiving section 2 is expressed as a percentage.
上記のいずれも、透光部１１を通り、第２の透光体２０
′に放射される光量は同じであるが、透光体１１と透光
Ｂ２１′の対向位置関係に応じて透光部２１′を通過す
る光量およびその通過光量のうち第３の透光体３０の非
透光部３２により遮光される量が異なり、受光部２に達
する光量は、第３，５図の状態、すなわち透光部１１と
透光部２１′の完全重合状態および１／２ピツチずれた
状態において最大、第４．６図状態、すなわち、両透光
部１１．２１′がそれぞれ１／４．３／４ピツチずれた
状態で最小となり、その最大と最小、最小と最大の開は
単調に変化する。In any of the above, the light passes through the light transmitting part 11 and passes through the second light transmitting body 20.
Although the amount of light emitted to the third transparent body 30 is the same, the amount of light that passes through the transparent part 21' and the amount of light that passes through the third transparent body 30 depend on the opposing positional relationship between the transparent body 11 and the transparent body 21'. The amount of light blocked by the non-light-transmitting portion 32 differs, and the amount of light reaching the light-receiving portion 2 differs depending on the state shown in FIGS. In the state shown in Fig. 4.6, the maximum and the minimum, and the minimum and maximum openings are the maximum and the minimum when the transparent parts 11 and 21' are respectively shifted by 1/4 and 3/4 pitches. changes monotonically.
以上は、特定の一つの透光部を通過する光量に注目した
ものであるが、他の透光部を通過する光量に対しても透
光部を通過した光量に対する受光部に戻る光量の割合を
示すパターンは同一（但し、位相はずれる）であり上記
の最大、最小の関係は変わらない。したがって、受光部
２からは、導入される光量に対応した電圧信号、すなわ
ち第１．第３の透光体１０゜３０と第２の透光体２０′
とが相対的に１７２ピツチ移動するごとに周期的に変化
する交番電圧信号が発生することになり、結局、従来技
術のものに比べて２倍の分解能を有する交番電圧信号と
なる。The above focuses on the amount of light passing through one specific light-transmitting part, but the ratio of the amount of light returning to the light-receiving part to the amount of light passing through the light-transmitting part also applies to the amount of light passing through other light-transmitting parts. The patterns showing are the same (however, the phase is shifted), and the above relationship between maximum and minimum does not change. Therefore, from the light receiving section 2, a voltage signal corresponding to the amount of light introduced, that is, the first . Third transparent body 10°30 and second transparent body 20'
An alternating voltage signal that changes periodically every time the two move by 172 pitches relative to each other is generated, resulting in an alternating voltage signal having twice the resolution as that of the prior art.
尚、上記実施例においては、投・受光部１′２と透光体
１０．３０の間、透光体１（１゜２０’、３０の各間隔
をそれぞれ透光部ピッチと同じおよび１７２倍とした場
合であるが、これに限定されるものではなく、適宜に選
定しても同様であり、また、第２の透光体の透光部２１
′、２１’ ・・・のピッチに占める割合も５０％よ
Ｉ）小さい適宜の割合としてよ本発明は、第１．第３の
透光体の間に位置させた第２の透光体の透光部をそのピ
ッチの５０％より小とし、かつ投光部の光源を散乱光源
とすることにより従来技術の２倍の分解能を有する出力
を取り出すようにしたものであり、高分解能化が制作面
、経済面のいずれの面でも容易となり、高分解能な回動
角、距離の検出が容易に実現される。In the above embodiment, the distance between the light emitting/receiving part 1'2 and the light transmitting body 10.30, the distance between the light transmitting body 1 (1°20', 30') is the same as the pitch of the light transmitting part and 172 times the pitch of the light transmitting part, respectively. However, the case is not limited to this, and the same can be done even if an appropriate selection is made, and the transparent part 21 of the second transparent body
', 21' . . . occupy 50% of the pitch. By making the light-transmitting parts of the second light-transmitting body located between the third light-transmitting bodies smaller than 50% of the pitch thereof, and using the light source of the light projecting part as a scattering light source, the light transmission area is doubled compared to the conventional technology. It is designed to output an output with a resolution of , which makes it easy to achieve high resolution both in terms of production and economy, and to easily realize high-resolution detection of rotation angles and distances.
第１図は本発明の実施例を示す正面図、第２図は従来技
術を示す正面図、第３〜６図は本発明の動作説明図であ
る。
１′：投光部 ２：受光部
１０．２０，３０：透光体
１１．２１’、３１：透光部FIG. 1 is a front view showing an embodiment of the present invention, FIG. 2 is a front view showing a conventional technique, and FIGS. 3 to 6 are explanatory diagrams of the operation of the present invention. 1': Light projecting part 2: Light receiving part 10.20, 30: Transparent body 11.21', 31: Transparent part
Claims (1)
透光体を挟んで投光部と受光部を配設し、第１、第２の
透光体の相対移動量を光電的に検出するようにした光電
式透過型エンコーダにおいて、第２の透光体を挟んで第
１の透光体の反対側に第１の透光体と一体化した第３の
透光体を設け、第２の透光体の透光部はそのピッチの５
０％より小とし、投光部の投光は散乱光としたところの
光電式透過型エンコーダ。1. A light emitting part and a light receiving part are arranged sandwiching the first and second light transmitting bodies each having a light transmitting part formed at a predetermined pitch, and the relative movement amount of the first and second light transmitting bodies is determined. In a photoelectric transmission type encoder that performs photoelectric detection, a third transparent body is integrated with the first transparent body on the opposite side of the first transparent body with the second transparent body in between. , and the transparent part of the second transparent body has a pitch of 5
This is a photoelectric transmission type encoder in which the light emitted from the light emitting section is set to be smaller than 0%, and the light emitted from the light emitting part is scattered light.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15106884A JPS6129718A (en) | 1984-07-20 | 1984-07-20 | Photoelectric transmission type encoder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15106884A JPS6129718A (en) | 1984-07-20 | 1984-07-20 | Photoelectric transmission type encoder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6129718A true JPS6129718A (en) | 1986-02-10 |
| JPH0253728B2 JPH0253728B2 (en) | 1990-11-19 |
Family
ID=15510601
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15106884A Granted JPS6129718A (en) | 1984-07-20 | 1984-07-20 | Photoelectric transmission type encoder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6129718A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6426162A (en) * | 1987-07-22 | 1989-01-27 | Matsushita Electric Ind Co Ltd | Position detector |
| EP0683231A1 (en) | 1994-05-20 | 1995-11-22 | Nippon Shokubai Co., Ltd. | Process for production of L-aspartic acid |
| US5783428A (en) * | 1994-07-19 | 1998-07-21 | Mitsubishi Chemical Corporation | Method of producing fumaric acid |
-
1984
- 1984-07-20 JP JP15106884A patent/JPS6129718A/en active Granted
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6426162A (en) * | 1987-07-22 | 1989-01-27 | Matsushita Electric Ind Co Ltd | Position detector |
| EP0683231A1 (en) | 1994-05-20 | 1995-11-22 | Nippon Shokubai Co., Ltd. | Process for production of L-aspartic acid |
| US5783428A (en) * | 1994-07-19 | 1998-07-21 | Mitsubishi Chemical Corporation | Method of producing fumaric acid |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0253728B2 (en) | 1990-11-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4465373A (en) | Encoder | |
| US6359691B2 (en) | Device for measuring translation, rotation or velocity via light beam interference | |
| US8124928B2 (en) | Optical encoder comprising two pattern arrays and several bell shaped light guides | |
| JPH0245126B2 (en) | ||
| JP4266834B2 (en) | Optical encoder | |
| JPH0248928B2 (en) | ||
| JP3170902B2 (en) | Signal processing method and encoder using the same | |
| JP2004191087A (en) | Optical encoder | |
| JPH087082B2 (en) | Optical encoder | |
| JPH04157319A (en) | Encoder utilizing silhouette pattern | |
| US3244895A (en) | Shaft encoders | |
| JPS6023282B2 (en) | Relative displacement measuring device | |
| JPS6129718A (en) | Photoelectric transmission type encoder | |
| US6759647B2 (en) | Projection encoder | |
| JP2001201369A (en) | Photoelectron system | |
| JPH08233608A (en) | Optical encoder | |
| JPH0237963B2 (en) | ||
| JPS5828615A (en) | Measuring device for extent of shift | |
| JPH09243336A (en) | Angle detecting device, and on-head image display device | |
| JP2004029019A (en) | Optical position sensing device | |
| JPH11118422A (en) | Dimension measuring device using moire fringe | |
| JP2000227346A (en) | Optical encoder | |
| JPS6129717A (en) | Photoelectric reflection type encoder | |
| JP4343350B2 (en) | Optical encoder | |
| JPH0411807B2 (en) |