JPS5886504A - Focus detector - Google Patents

Abstract

PURPOSE:To eliminate an error in focus detection due to chromatic aberrations without limiting a wavelength range and brightness by generating a focus detection output through a lens having chromatic aberrations, and correcting the output through the output of a color temperature measuring means. CONSTITUTION:A focus detection part 1 detects deviation from the focusing position of a lens L by light transmitted through a lens L to generate a focus detection signal. A color temperature measuring measuring device 1 measures a quantity regarding color temperature. An information transmitting means 3 transmits information on chromatic aberrations of an interchangeable lens L. A focal point correcting device 4 calculates the amount of focal point correction from the color temperature information and chromatic aberration information and adds it to the deviation from the focusing position to generate a correct focusing signal for light having wavelength within a prescribed range, thereby outputting it to a lens driving device 5 and a display device 6. For infrared-ray photography, an infrared film selector 7 imposes infrared aberration correction upon a correct focus detection signal at a visible part through correcting device 4. Consequently, an error in focus detection due to chromatic aberrations is eliminated without limiting the wavelength range and brightness.

Description

[Detailed description of the invention] Motoya - Hiro Focus detection device e41t = "Camera (D55 Lens Hibiki tA has chromatic aberration - one difference by two! Excluded focusing machine - device ◎ No inspection &fi device 1; is 1 Chromatic aberration! 4# Il1 military light incident through the lens, liquid length in the visible region and outside the visible region The output of the party element element 12 is 44
There are some that perform the 11th exit.

Due to the color retention of the lens, smoked with such iron creases.

^ Directly placed light 1; On the other hand, with different focusers alIv, the angle is 11 and 5! Silicon photo as an optical element
The color temperature of the tungsten run 1 tatami was 1/J when illuminated with a low source, and the -1 1 l zero body [
Focus detection will be different depending on the chromatic aberration of the lens compared to a trunk illuminated with a source of high color temperature such as starlight or fluorescent light. This chromatic aberration is particularly large in long focal length lenses. Therefore, when a single-lens reflex camera is equipped with a long-focus interchangeable lens, the light incident on the object through the long-focus lens is photoelectrically converted by the receiving element like Q), and the focal point is detected by the photoelectric output of 7. The focus detection error due to the chromatic aberration becomes noticeably large. This focus detection l14IE may vary depending on the amount of lens extension 6: several i microns.

Next, we will discuss the relationship between this chromatic aberration and the occurrence of focal lateral a3I141IcD.

FIG. 1 shows the relationship between the wave length distribution and the wavelength for each one-element source illuminating the l[ donor. Strict-line relative component distribution! Graph Bu under fluorescent light
Evidence source, graph c line A source area tungsten lamp etc. light i respectively shows T0 @ 2-, spectrum aI of spectral sensor V spectral sensor t! , and its IIA direct peak line a 800
Infrared region 4 in vm: Yes. The 3rd diagram is as follows.

Indicates the chromatic aberration of the photographic lens. yt, imt represent light with a wavelength in the visible region, and light Ht represents an element with a wavelength in the infrared region emitted from the same light source as the light source T0. From the same figure, the focal point f of the light source 1 is It can be seen that only the Δ field is affected by the position of the focal point f' of the infrared light l'. Summary 4all shows the relationship between the chromatic aberration of the photographic lens and the translation length. The vertical - of l1l(2) is the 6th
The visible light 6 pair shown in the figure also shows the focal shift ΔYang, and the horizontal axis shows the translation A. It is clear from Figure 1Agl-NLII4 that the graph D of 54-Series 2-QJ% has a silicon photocell vM and the focus is detected by a bamboo. The illumination of the subject is determined by the chromatic aberration ζ of the lens shown in Figure 31 and Figure 4.
Smaller than IK roof Δ2.

However, if the ratio between the two infrared sources is large, as shown in graphs B and C, the chromatic aberration of the lens becomes large. Therefore, the detected 1m point Hiroshi 6 Peng's f (the two closest positions, the possible Im party 6
;The focus pot lid Δt becomes larger. As a means for adjusting this focus detection distance IllΔ-, there is a filter that can only communicate with II'yt. established, it-2 therefore WI41
It is conceivable to perform focus detection using a transparent source other than the infrared optical and visible source, which is the key point of 1. However, to do something like this (;T) is to take advantage of the information from the external telephone C;, and therefore, it is possible to use the #Li1k region or the visible light region of the camera, which is easy to use. There will be some noise during that time.The following -2, this filter & used 10,000 fk(:,-')''
C review 11As=@@T6m@2- graph p″eyi#
Silicone photosensitive resin 5pLS, @s
- When using the % communication filter shown in the graph 1, the spectral sensitivity of the photocell is equivalent to 1; as shown in the graph 2-2; The naivety of doing so decreases, and the dust inspection collapse error due to #outside shyness ^ 1 becomes small joy. ] [Compiled by 4 filters! - As shown in graph 1, IIL length 400 to 700 ssa a visible area only 6
The photocell's sensitivity *v, w@ is that the general ζ-ni lens is designed to have 12 aberrations for visible light, so it also has 12-color convergence as shown in Series 41 II. 400
In the visible ridge length region of ~70F-, it is relatively flat, and the focus detection heat difference due to nine chromatic aberrations is 112, which is almost negligible.

Therefore, the simplest way to eliminate the unchecked HILIIivt due to chromatic aberration may be to detect focus using a photocell that has the characteristics as shown in graph 1 of 11B2-. However, The light source is 1-
Graph B, @4 of O Hibiki: A place where we meet a lot of infrared light 6;
Failure to make full use of infrared light may result in a lack of detectable I11.

Unrelentingly, it is possible to detect directly under the direct exposure area and brightness @ V - 1 envelope II (2 focus detection MII & removal hinge, also known as IL 1 and 7, #tJ
It has become a masterpiece like the one below. In other words, one breath detection device has 8 units! T-Shoulder lens, has one directivity for visible light from the subject and light C other than the visible light.

A focus detection unit that outputs non-inspection outputs to a subject by using those elements incident from the subject through a lens W.

Copy% Kara no color sgtstt'mmt, Soa color s
ixg: An envelope setting means for relaxing the output of 1llI%.

and a correction means for correcting T so that the 'S point detection output according to the knee-related output G) is as follows.

The present example will be described below with reference to weighted -mV.

A summary of the construction of a focus detection device according to an example of the present invention is summarized in 6-
52 is shown. This device is one of the best when used as a camera gJk. The focus detection section 1 expands the width of the lens Lv and the width of the lens VIl due to the communication between the lens Lv and the lens Lv. *Inspection swelling part 1
-2 units of charge, electric conversion element 9 For example, silicon photo die t-tg or visible range; infrared C2 also IIA [
v to have a; g check as Zheng 1 or meet infrared light xt'
When performing pointless detection in lIm, lens L is connected to C2.
Due to the infrared plate roofing, the focus detection unit 1 was not inspected - IN4#
In the case where focus detection is performed using only visible light t'giI, focus detection No. 1 (for -Wt) S point detection - Ill causing a difference. The device 2 transmits the information related to the copy body 9. The information body R3 is exchanged, and the lens I, a color convergence is transmitted. Focus position The correction mortar 4 calculates the relative output and lens color ew11 or biIA point position and correct amount, and checks the S inspection-11 from the vl focal position to the thread jiiI.
, then F51r fixed axle's ridged light C; for this, the correct focus is created T0, and the two lenses, the pot holder 5 and the translation device 66 are separated. ＃In the case of Sotoorikage 1
;, the infrared filter At rect 7 is connected to the signal t'ai kashie supplement J
Efil14g: Therefore, correct visual inspection aIs et al. 5; Photographic lens Lj:, J@a Further addition of compensation by the amount of infrared absorption, clear infrared photograph! Photography possible - 2T
Ru.

For M-shielded reflex cameras, the value of lens L and 5 (l\
The hand IIL that outputs the information is provided on the interchangeable lens body 17, and the other Sat is provided on the camera body i2.

Next, the color temperature [#aji! There are two machines 2C in machine 2 and will be explained.

Figure 7 shows the party line system with the two-color Kame-Oki-ranomi device 2.

This optical string is a current collector lens 8. For example, the visible part 4491111 and J in the visible part 4491111 and J of Fig. 1 are provided with a bony man-selection mirror 9, which receives the visible part with the main -2 rich light V* light -10, and receives the infrared light.藝'i 4=, tmu light 15
1! jEI111 “1: Party ft,” thllNILl
It's two. a) 6 for light strings a; Visible light only W
A filter 121 is provided to allow AT to pass through, and amII legs are also provided. Also, regarding the a meeting C- of Haruka Translated by Miller and Hiroko Tomitsu, there is a spectral sensitivity like No. 9- [A commercially available color T-ton that provides two bone-like outputs! -Use it as a substitute for a filter◆
It is also possible. s t, im shows the circuit of the paring lL column noodle device 2 at', 81mt3m position ##l1410. .

10j, 11g, 114v to the installation of this series 8-m
I'm ash. The visible part is king (two rich light - one, so my dog 1)
110 (:, the photoelectric power that I lost is converted into the number yI!g from the operational term 111@1jl2, and the voltage 6 becomes Vν; it is converted. The light rich in infrared st' 62 is received by I111r-I. The sense current is logarithmically transformed by operational amplifier @14.
It is responsible for the voltage that is $. The difference-increase width s15 outputs a quantity lV4: m (V9-mi)+VrY which is related to ε2 in addition to the excessive off-tit voltage Yvj:a. or.

Terminal 16i; Using the output VVn, m output (JIIIll of the film) T'ti#, it is also possible to use the party system shown in Figure 10 instead of the party system shown in 7IO.
It can also be used.

The optical character system shown in FIG. Jucho Haruka Selection Mirror 9. Visible light photodetector 10.
and an infrared receiving element 11', and X-4i) output V
make a corner.

A specific example of the machine housing 4 of the present invention and this Iku Hatobe will be explained using FIG. 11, 1112-. Mayuki's 1lIKNamotsuirokiKflaSeikikan2 or bOutput fe, gourdf&- related quantity #-Ya (output vC of m soag8 figure of this specific example
[The inverted negative output is output from J or 5e* terminal 18 of lens seat 17. The interchangeable lens body 17 has an awL value f1.Pa vJT resistance vnim as a parameter indicating the chromatic aberration bone property of the photographing lens.
do. The color temperature information t# corresponding to the color temperature 1; of any subject is generated. As shown in the figure, one end of the resistor Kfm is terminal 184 and the other is terminal 196; Owns a genus.

Terminal 20 reference value position 111E-position 4a) Electrical voltage conversion Zheng 211 knee aalit&, ζalf conversion 1121 [11
EjEVgvm力” ”e ell-俟-214D
jfi power'Im-ha#ma@m-ma-1 Ma・"'
(1) It is the quantity given by t■ de1. Voltage vajY# that satisfies this formula
The equation for s12m(1) is 8 as shown in the graph shown. $1126 is horizontal @ den IE V
＠、线s t=voltage vg t'lE pressure vg yINJ6 blli breath inspection - take the difference 2, no inspection - 111, 錬电变子, and the sense and perception is as shown in the 2nd garden graph 1 Things vI! An example of using vaa*b is shown below. aS body V as a light source that becomes invisible as a light source, @ftea, 11') Nbu vI! The sound used.

The voltage V6 outputted from the encapsulation field w1 and the definition field 2 or b is 10V・(19V-17Ys'n), and (Weゝ1)
Marq v, (4# is the most amorphous; it can be considered that they correspond,) 84- is an aberration %*t'w of the aberrations L [through the graph B of Focus detection when detecting a focus using a party element with such a minute-tsg frame-11
6 is 宷掬 or calculation C Niyore respectively l112■a
, becomes a. In other words, if only 111 layers of Vg layer are used, C fluorescent lamp) 1; will not be affected by chromatic aberration, and the ratio of daylight and W lamp infrared rays will increase. Insect 2 grows in size.

This situation is approximately illustrated by a folded line 11 graph like 〇 in Volume 12. From this graph M, the valley voltage Ve
4. It becomes possible to estimate the corresponding focus detection error Δ2, and it becomes possible to correct the detection error v11Il due to the monochromatic aberration 62.

II II (:, is a hunch.

At'st, the graph shown by a chain link shows V, -V
g characteristic, and the photographing lens L [chromatic aberration parameter rz, press button wcv to satisfy 7, l2t'1
．． The value of rjl [Determine. The output Vg thus obtained
Smoke, multiplexer function/D conversion 1122 function/D
From Exchange-1;

Vz) When it is O, it remains at 7 and undergoes Mu/D conversion.

When Vg<0, the resulting output becomes a constant value of 0, and h/D g￟＠eVg C＠＠”16m force is the final argument 1
Figure 2: The disgusting boneiness of V Ii ■, or the fact that Ii Yu is obsessed with it C; becomes. Multiplexer and A/D Conversion 1,122 yen is required for multiplexer and A/D conversion [The arrangement of the exchangers shall be changed depending on whether the output signal of the focus detection section 1 is a digital quantity or an analog quantity.

113 shows the structure of the multiplexer and A/D conversion-22 when the output of the focus detection unit 1 is an analog signal. Here, the multiplexer and Mu/D conversion (to)
22, the analog multiplexer transmits the analog signal output from the focus detection unit 1 and the analog signal vs from the current-voltage converter s21 to the A/D converter in a V time-division manner, where it is converted into a digital signal after being converted into a digital signal. become. Next, this digital signal is transmitted to the microphone computer 23.

Summary 148vI is the multiplexer and A/D conversion when the output of focus detection s1 is a digital signal @@22
The structure of First, an analog signal from the current/voltage converter 21 is converted into a digital signal by the /D converter. For a long time.

The digital signal from the trap 6;
Here, the data is temporarily divided into the memory card 114 and transmitted to the microcomputer 23C.

The digitized focus detection signal obtained in this way and the correction signal obtained by digitizing the applied voltage Vg are added with uniform weight in the microcomputer 254; #V display 124 and drive * device 25&2 output. and according to the output of 7-2 display 1124 shows the focal articulation m, 111
111111m25tt Move the lens L to the focal position.

In this way, the value zero body element 6 reveals the abundant light.

This 962 pairs of lenses L41) depending on the chromatic aberration ＼
Correct the focus detection signal by an amount equal to Δz-2.
11 focus detection for bi-focusing.

T, that is, the correct focus detection value 4It' t t=obtain ζ
Of course, if a resistor r l + avt corresponding to the chromatic aberration of the lens mv is provided for each interchangeable lens, a correct focus detection signal V can be obtained no matter what type of interchangeable lens t'ia is attached.

Another specific example of the present invention will be explained using Figures 15 and 16. One voltage VO is supplied from the focal position correction device 4 to the input terminal 201 ≦2 of the interchangeable lens body 17 .

The terminal 201 is connected to the outputs 202, 203, and 204g2mm through resistors II rx, rtl, and r"s (1), which express the aberration characteristics of the lens L, respectively, and each output returns to the focal position wL? 1I positive device 4d; includes current/voltage conversion @ 211, 212, 2154 and outputs 9% current/voltage conversion @ 211, 212 degrees pressure.The yield characteristics (or resistance parameter 1" l + Is it possible to set up a fss rs in various ways?

The explanation will be made using the first 16- for one corner 1.

Figure 916 is horizontal @ g:, ai! Take the output vtJt of the long and chromatic slope field determining device 2, and take the aberration and focus detection - Δzv, and use the 5 & party light as the light source, 1 '%.
1K2allD, l at 16-V C"', respectively
, 10 senses I! Focus detection was performed from the V-hinged light receiving element-2.Q) Focus detection aberration vle El's
I"'2, also light - the V tt of the ringing sound that was used to close the door
= V e” 2nd figure in each of the 42.

1. Focus detection when performing focal point detection 'Used 1 Vs = Vc'' i 2, respectively, 2 gardens, 1, 10) Focus detection was performed by a light receiving element shouldering the spectral 5IjL flexibility.
(/, =”+= Niblot. Now, the graph 0 indicated by -1 is the aberration % of the photographing lens! (lK41
mJ't' is multiplied by 1, and this aberration characteristic mat
'Ier>, fl t- is used as a cutting parameter. rl, , , avg < Meushi ttne is shown in the infrared as a real T graph OC Overlapping straight sickle, that is, shown as a chain dot in the figure T graph Pt Considering, il length λ = 750 ss Q)
Single color 5t (Kotto 8V 6; yol 76o)
J c versus T infrared flit heavy th Z 7110
-1 Correspondingly, a predetermined conversion coefficient DA 62 is defined as a circle I1. The resistance value is good. In addition, De3 is the shadow of principal-two spherical aberrations @-2 for each photographing lens ≦; a certain amount of compositional aberration Δ2# of lens surface M that exists as a different stage
This is the 8th resistor of the T basket that satisfies the positive T. (ΔZao is a predetermined constant and is stored in RUM2) This will be explained with reference to the actual focus correction function. Focus detection s
1 to Q) s point detection notes 2 and color 11 degrees # constant iIA wrinkles 2
The signals V- and the shoulder image r-ve are appropriately selected by a multiplexer, sent to a ram/D conversion sieve, and stored in the memory of the microcomputer. When the output 2 from the focus detection section 1 is a digital quantity, it is inputted to the microcomputer 23 via a MU/DR converter by a multiplexer. ROM of microcomputer 25 (: is previously written as Seiko V)
Accordingly, the slope correction factor P is stored, and its value is calculated as follows: When the force is ft, aC or the 211Q graph D has the spectral correction, the corresponding output is ? The T graph Q shown by the broken heart with 1 is the aberration characteristic v of the photographing lens.
llwaT is slightly thicker than the graph P shown by the dashed-dotted line (
F=tl, and the spectral sensitivity tt# of the graph l in Figure 2 shows the corresponding output g, and Lllillml with 4' shows the T graph wind calms down to one point. 0,
It becomes s. Also, the graph shown by the dashed line r or negative &)1111
In case 1, the effect of aberration is almost zero, so one color is used.
Non-inspection mIK difference correction ∆IC smoke ∆Z6 = MAX
['% (AZ 75 (1IA zo) / f vc
”” Tonal. MAX IA in C, B)ktA,
There are 10,000,000,000,000 yen, which has a large value among b. The microcomputer 25 calculates (zJ formula (-17@Todoroki) and calculates the focal position deviation z6 and the dichroic aberration correction ΔZ6.
, and further corrected spherical aberration (corresponding T4 correction Δz
a vm L, "c Z -ΔZ C+aZ 4's child 'Jk-focus point output polarity code is displayed and outputted by the body device 6; Also, when the external oblique film selection in Figure 214 is matted - 2 Microcomputan 3 is further (2 ΔZ 711G correction 12MJL”c Z −Δ
Z c + ΔZa + ΔZ 76Q.

As mentioned above, 5: Fault #4 (accurate in a wide wavelength range and low brightness level because the focus detection is based on the chromatic aberration 42 and the chromatic aberration 42) It depends on the focus detection function.

[Brief explanation of the drawing]

Figure s1 is a diagram showing the relationship between the relative denominator distribution and the station master, as shown in the diagram. Figure 112 shows the spectral sensitivity of Seiko Toko. Figures 2 and 4 show the color convergence of the photographic lens. Line 5 (2) line filter V permeability semi-characteristics 1゜ Line 6w is a diagram showing the development of 1ltll of additional point detection eel weight of Ichigai Yoshin of the present invention - Line 711g and Line 8 Figure 4 color is once beautiful The story of the sardines, i
A diagram showing gt'. Song 9 shows the original character of the sword. Chicken 10alG shows another Kuji thread V of Irokago Naoaki Ashi Eel Box -1 lit 1lill is a diagram showing the pointless detection eel weight of the concrete power of this dull light. Figure IA12 is the output of the negative section of the 11th m mark, bot-1 815w, and Figure 14 is a diagram showing the multi-7 Lexa and Mu/D quality Qin-V composition. 1511iQ# A diagram showing a focusing device of another five-axis-v concrete lens. Figure 16 is a diagram showing the output of the apparatus shown in Figure 15. [Kou Mourning Code Q) Explanation] L・・・・・・・・・・・・・Lensto・・・
......Focus detection section 2...
・・・・・・Baso IIt Glue Feet Means 4・・・・・・・・・・・・
...Nesho+Danmitujin spectral distribution figure 4 - f'5 figure, f'12 figure 13 figure 14 figure 15 figure 16

Claims (1)

[Claims] A lens having monochromatic aberration characteristics. The focus detection output that outputs the two pairs of objects C using those zero points is the focus detection output that outputs the two pairs of objects C using those 0 points. Color @mt'at is added, and the color 11 zone temperature sense-related output IN is generated color turtle position constant means, and title color turtle 11j (Knee related Todoro car; accordingly, *Ki focus detection output V place) Haya - Kencho C; Detection of S point of the subject I
Equipped with a correction hand RY that corrects it to I4# vII
#Mildew and hinge focus detection device j 2, Focus detection device described in %lPFmylc's IS-Collection 1 Lecture-2. The focus detection output vJ!yrWl#Lik聰-, and g
Focus detection button 1 whose purpose is to correct the W number that detects the inherent consideration of the writing angle.