JPS58123160A - Optical function generator - Google Patents

Abstract

PURPOSE:To obtain a desired function signal, by applying an electric signal corresponding to a change of form of a pattern to an electronic circuit including a differential amplifier. CONSTITUTION:The light emitting elements 3a-3b' having 180 deg. intervals in terms of an electric angle are connected in series. At the same time, the photodetecting elements 4a-4b' corresponding to the elements 3a-3b' are connected to both minus and plus input terminals of operational amplifiers 5 and 6 of differential amplification type respectively. In addition, the variable resistors R1-R4 are provided in parallel for photodetecting control of the elements 4a- 4b. As a result, a change of form of a pattern can be converted into electric signals having phases different by 90 deg. from each other and in terms of an electric angle. Then an optional function can be decomposed to a sine wave by the Fourier decomposition to ensure an application as an optical function generator.

Description

[Detailed description of the invention] The present invention relates to an optical function generator.

A rotating glass plate l is shown in FIG. 1a, and is provided with a transparent butter 7/a having a sinusoidal shape pasted along its periphery. If the electrical angle for one period of the waveform is 3600, divide it into 5 equal parts as shown by the arrow, oo, de 0°, 1t.
o0. Body 0°.

340". This angle is of course not the same as the mechanical angle, and is mechanical angle n1eJ40' electrical angle - 辅J4Q' outer diameter of the disk Hmr + acase. Also, as shown in Figure 1, the fixed disk - This corresponds to Fig. 1 a.Slits a, b, a', and Jb' are provided at the 0° position of 0.too, izoo, and depth.

Next, as shown in FIG. 1C, the axes of the rotating disk l and the fixed disk coincide, and the slit cores a, b, and aI are made.

The outer edge of the rotary disk I is aligned with the outer circumferential surface of the rotating disk I with an interval [Light-emitting elements J a e J b e
Ja', Jb' and light receiving elements 1a, lb, reference m', lb
(Only J and la are shown in the figure) These rotating disks I and fixed disks are placed in between.

In this way, by rotating the rotating disk I, the light emitting element Ja
The light from Jb, Ja', Jb' forms a pattern/
Transparent part of a, fixed disk - slintco8. Cob.

Light receiving element 4 through core a' and Jb'! a, visit a'
, lb' can be changed to the following output voltages.

VIIa = acos#-1-A@@11 (1)V
eb = β5iIe + B @ @ e (
2) V+a'=-α'CQS#+A' @*@
(31vIlb' = -β'siI j ten B
'Φ ・ ・ (4) Next, the light emitting elements Ja and 3 a/, J are separated by /lO° in electrical angle.
Fig. 1 shows an electronic circuit wiring diagram of an embodiment of the present invention in which the light emitting elements 3a and Jb' are connected in series.
/, 3b and Jb', the light receiving elements a and la', 4I
b and 41b' are respectively differential amplifier type operational amplifiers, that is, differential amplifiers! , 4 to 11 of the input terminals. In addition, variable resistors R/ + Rx* R3* are installed in parallel for adjusting the light reception of each light receiving element la, la', lb, and 41b'.
Insert R41. Thus, the variable resistances R,,R,,R,
, R4I, α=β=α′=β′, A
-B=A""B'. In this case, V<la = αoas#10Aass (5) Vub
=α5iIe 10A −@@f61VII
a'=-α(6)θ+A ,,-(7)v*b'
=-αsin #+A...
(8) Next, with differential amplifier 5.6, Vfa and V41a'%V
As a result of differential amplification between yb and v41b', MA -
V4ca V4I&' -J k αCoSe
(91vBz vvb −Vlb' = J kal
=s αs is the gain of the differential amplifiers j and A.

Therefore, there are five steps to convert changes in the shape of the putter into electrical signals that are electrically different in phase by 900 degrees.

The above is a sine wave pattern.
In contrast to the sine wave shown in figure a, the same triangular wave can also be used.

Here, if the period is 3400, its % period is toO.

Thus, the configuration according to the present invention is simple, can be manufactured at low cost, and can be operated with a DC power source. Furthermore, with the development of NO processing technology, it is now possible to process disks with high precision, and the precision of the function is also higher than that of conventional methods. Also, since no contacts are used, reliability is high. Furthermore, by changing the light intensity of the light source with an arbitrary time function, the output function can be easily modulated into an arbitrary time function. Now, the function of the change in the light amount of the light source is L (ωt), and the function of the pattern is f (θ).
Then, the output function F is modulated as F=L(ωt)·f(#). Here, ω is the angular velocity of the change in the light amount of the light source, and 0 is the rotation angle of the input shaft of the function generator.

Also, by drawing a pattern drawn on the circumference on a linear scale, for example, as shown in Figure D a1, a linear function generator can be used that generates a function in response to linear movement. Can be done.

[Brief explanation of the drawing]

Figure 1a is a front view of the rotating disk l, and figure 1b is a front view of the fixed disk.
Figure C is a side cross-sectional view showing the rotating disk l, fixed disk, and light emitting and light receiving elements. Waveform diagram, Figure dA
, b are a pattern drawn on the circumference -F and a pattern drawn on a linear scale, respectively. In the figure, l is a rotating disk, C is a fixed disk, la is a sine wave pattern, Ja, Co a/, Co b, Co b' are slits, and 3 pieces e
J a' e J b * Jb' is a light emitting element,
Da a. Da a1. Da b and b' are light receiving elements, and j and A are differential amplifiers. Patent applicant Tamagawa Seiki Co., Ltd.

Claims (1)

[Claims] l A rotating disk including a pattern of transparent or opaque parts having the shape of an arbitrary periodic function including a sine wave along the periphery, and a fixed disk including slits provided at 900 intervals in the circumferential direction. A large number of light-emitting elements and light-receiving elements are placed side by side with their axes aligned and spaced 900 meters apart with a fixed disk and a rotating disk sandwiched between them. An optical function generator whose mission is to generate a desired function signal by applying an electrical signal corresponding to the change in shape of the object.