JPH0517497B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a crystal orientation measuring device, which can be used in-line in the mass production polishing process of bonded diamond needles used in capacitive video discs, digital audio discs, etc. It is suitable for a rapid crystal orientation measurement device for 100% inspection to exclude diamond crystals whose orientations are greatly tilted from the set direction and twinned diamond crystals.

As crystal orientation measuring devices, a Laue camera using an X-ray film as a detector and a four-axis automatic diffractometer in which a sample crystal can be rotated about four axes have already been developed and are in general use. However, determining the crystal orientation of diamond using these devices requires more than 20 minutes per sample. That is, the film method requires at least several minutes for exposure time and approximately 30 minutes for development time. Furthermore, it is necessary to analyze the diffraction photographs using a Greininger chart, etc., and there is a process that requires relying on human visual judgment, making it difficult to apply to 100% inspection on a mass production line.

The four-axis automatic diffractometer uses an X-ray detector and can be controlled by a computer, so it does not require much human judgment and has high measurement accuracy. However, in order to measure X-ray diffraction reflection, the angles of at least two or more rotating axes must be moved little by little independently, so the measurement time is about 20 minutes, and it is difficult to incorporate it into a mass production line. This method was inappropriate as a method for measuring the crystal orientation of processed products.

The purpose of the present invention is to inspect all unprocessed diamond chips on a mass production line, and quickly determine the diamond crystal orientation relative to the shank axis on which the diamond chips are placed, in order to detect defective products and obtain information to stabilize fine polishing workability. The present invention provides a crystal orientation measuring device for determining crystal orientation.

In the present invention, the target crystal is limited to a cubic crystal system such as diamond, and the X-ray optical system is devised so that the rotation angle of only one axis corresponds one-to-one to all the X-ray diffraction reflections of a specific index group. This enabled rapid collection of observation data. In addition, we experimentally discovered that crystals that are difficult to polish are either fixed to a holder at an angle that deviates greatly from the predetermined orientation, or are twinned. A data processing program that calculates the three parameters of crystal orientation from angular data and a determination program that utilizes the fact that twin crystals cause X-ray diffraction at different angular intervals from single crystals can quickly detect twinned crystals and determine the crystal orientation. This makes it possible to determine whether the deviation from the value is greater than the allowable value.
That is, the object of the present invention is to provide an X-ray source that can obtain X-rays of a specific wavelength, a collimator that narrows the X-rays emitted from the X-ray source, and a collimator that can detect only the diffracted X-rays of a specific surface index group. An X-ray detection system having an X-ray detector, a semicircular slit installed in front of the X-ray detector, and a shutter that closes a part of the X-ray detector when necessary, and a collimator for detecting sample crystals. A mechanism that allows the sample crystal to be rotated at any speed using a single rotation axis perpendicular to the finely bundled X-rays, which is installed at the midpoint between the X-ray beam and the X-ray beam, and rotates the crystal around the axis while irradiating the X-rays. A mechanism that can measure the rotation angle at which the bragging condition is satisfied by detecting the diffracted X-rays obtained when the bragging condition is satisfied for a specific crystal plane with the X-ray detection system, and the four rotation angles measured by opening the shutter. The presence or absence of twins and the tilt angle can be determined only from the measured values of the angle, and in addition to the above-mentioned four rotation angle measurements, the 180°
This is achieved by a crystal orientation measuring device equipped with a calculation mechanism that can determine the crystal orientation of a single crystal from the measured values of two rotation angles of degrees or more.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing the arrangement of main parts of a crystal orientation measuring device according to the present invention. In FIG. 1, X-rays 1a generated from an X-ray source 1 are made into a fine bundle by passing through a collimator 2, and irradiate a diamond chip 4 joined to a shank shaft 3. The X-ray 1a transmitted through the diamond becomes a beam
Absorbed by stopper 5. The shank axis 3 rotates φ around the axis, and X-ray diffraction occurs only when an angle is reached that satisfies the geometrical conditions for establishing Bragg's law. Among the diffracted X-rays 1b diffracted by the crystal planes of the diamond chip 4, those with a specific plane index are selected by the semicircular slit 6, and incident on the X-ray detector 7, which is arranged at a distance so as to output an output. Set L. Also, between the semicircular slit 6 and the X-ray detector 7, an X-ray detector 7 is inserted when necessary.
A 1/4 shutter 8 is provided to close a portion of the shutter.
The distance L is determined from the wavelength of the X-ray, the surface index of the diffracted X-ray, and the radius R of the semicircular slit 6. Here, an example will be shown in which the X-ray is M ₀ Kα ray, λ=0.7107 Å, and the plane index is {111}.

Since the lattice constant of diamond crystal is a ₀ = 3.568 Å, the diffraction angle θ is calculated from Bragg's law as θ =
It is found from sin ^-1 (√3λ/2a ₀ ), and θ=9.93°.

From Figure 1, the relationship between L and R is tan2θ=tan19.86°=
It is given by R/L. The width of the semicircular slit 6 is determined by considering the spread of diffracted X-rays, fluctuations in the lattice constant of the diamond crystal, temperature changes in the distance L and radius R, etc.
L=41.5mm, R=15mm and 1mm.

Since the diamond micropolishing process is performed based on the center of the shank axis notch surface 3a and the shank axis 3, the relationship between the axial direction of the crystal axis of the diamond chip and the shank axis 3 is as shown in Fig. 2. Notch surface 3a⊥Diamond crystal axis a ₁
and shank center axis (Z) diamond crystal axis a ₃
It is desirable that

The orientation of the diamond crystal with respect to the shank axis is shown in Figure 3.
All you have to do is find the parameters of the species, α, β, and γ. In FIG. 3, a ₁ , a ₂ , and a ₃ are unit vectors of diamond crystal axes, which are perpendicular to each other. Also, X, Y, and Z are axes attached to the shank axis,
X is perpendicular to the notch surface 3a of the shank shaft, Z is coincident with the axial direction of the shank shaft, and Y is an axis perpendicular to X and Z. In Fig. 3, α is the inclination of a ₃ with respect to Z, β is the angle of the XY in-plane component O′T′ of a ₃ from the starting line OX, and γ is the inclination of the XY in-plane component of a ₁ .
This is the angle with OX as the starting line.

(111) ^* and (111) ^* are the diffraction vectors of diamond crystal planes, (111) and (11) respectively.
It is perpendicular to 1). OT′---→, OO′――→ is (11
1) ^* ,
(111) ^* This is the projection of the diffraction vector onto the XY plane, and the angles formed by the starting line OX---→, OT′---→, and OO′---→ are w _{i and} w _j , respectively. Using the apparatus shown in FIG. 1, X-ray diffraction is observed when w=θ+w _i and w=θ+w _j . Now, (111) ^* −(111) ^* vector≡r ₁ r ₂ ―――→≡OT″――――→≡2a ₃ ∠r ₁ or ₂ = 70.5
Since the conditions such as 3° hold true, (111) ^* , (111) ^* , (111) ^*
and (111) *Measure the w rotation angle corresponding to ^* ,
Three types of parameters, α, β, and γ, can be determined.

In FIG. 3, when the rotation angles of the diamond (111) plane are w _i and w _j , this means that there is X-ray diffraction due to the diamond, and there is an output to the X-ray detector. Now, if we can determine the angles w _i , x _i , w _j , x _j in Figure 3, we can easily calculate the deviation angle (α, β, γ) from the crystal orientation setting using the following formula. .

cosα=r ₁ O′+r ₂ T′/r ₁ r ₂ =√3/2(sinx _j −si
nx _i )…(1) tanβ＝S″T″／O″S″＝cosx _j sinw _j −cosx _i sinw _i
／cosx _j cosw _j −cosx _i cosw _i …(2) tanγ＝hm／Oh＝cosx _k sinw _k ＋cosx _i sinw _i ／cosx _k co
sw _k +cosx _i cosw _i ...(3) Here, the relationship between x _k and x _i in equation (3) must be x _k · x _i <0. That is, (111) ^* + (111) ^* =
2 (100) ^* or (111) ^* + (111) ^* = 2 (100) ^*
Take advantage of the relationship between

In this way, the three azimuthal angles (w, x) of X-ray diffraction
If can be measured, (α, β, γ) can be easily found. However, when trying to find two angles,
The crystal must be rotated about two independent axes, which not only complicates the measurement equipment but also requires a long measurement time. Therefore, in the present invention, a method of determining the deviation angle (α, β, γ) using only one-axis rotation was devised and applied.

X-ray diffraction by a diamond single crystal occurs when extremely limited geometrical conditions are satisfied. Therefore, when the relationship between the rotation angle φ of the shank shaft and the output of the X-ray detector is expressed, a sharp peak is observed as shown in FIG. Assuming that the angles at which these peaks are observed are φ ₁ , φ _{2 .} . . in order, eight peaks from φ ₁ to _{φ 8} are observed from single crystal diamond.

On the other hand, {111} ^* diffraction of diamond occurs according to Bragg's law given by the following equation, so
The angle between the incident X-ray beam and the diamond (111) plane is θ
Observed when tilted.

sinθ＝√3λ／2a ₀ …(4) Here, a ₀ of diamond = 3.568Å, M ₀ Kα
Substituting λ = 0.7107 Å, θ≒9.933°.
In the apparatus shown in FIG. 1, the relationship among φ, w, and θ is expressed as φ _i =w _i −θ (5).

In Figure 5, if (X, Y, Z) is the same coordinate system as in Figure 3, and (u, v, w) is the coordinate system of the crystal axes, then the XY plane and the XY plane when rotated by w in the XY plane
The angle δ formed by the UV plane is given by the following formula.

sin δ=−cos(w−β) sin α (6) Consider eliminating the angle x in equations (1) to (3) using the relationship in equation (6).

In Figure 6, o-p-t is the XY plane, o-s
−q is assumed to be included in each of the uv planes. Also,
or ₁ ---→ and or ₂ ---→ indicate the X-ray diffraction vectors as in FIG. 3. Now, if the intersection of _{1 2} with the o-s-q plane is f, then (111) ^* and (111) ^* of the cubic system
From the geometric relationship of diffraction, _{1 2} is orthogonal to the o-sq plane, and f is the midpoint of _{1 2} . Also, the angle formed by (111) and (111) of diamond is ∠r ₁ or ₂ ≒
It is 70.53°. Now, if ∠r ₁ or ₂ = 2η, then ∠
for ₁ =∠for ₂ =η≒35.26°.

In Figure 5, ₁ = ₁ sinx ₁ …(7) = ₁ cosx ₁ tanδ ₁ …(8) ₁ = ₁ sinη …(9) ₁ = ₁ −= ₁ /cosα …(10) (7), (8) , Substituting equation (9) into equation (10), ₁ sinx ₁ − ₁ cosx ₁ tanδ ₁ = ₁ sinη／cosα…(
11) Since equation (11) is generally valid, we obtain the following relational equation.

sinx−cosx tan δ=sinη/cosα (12) Here, if sinx can be expressed by an expression of only δ, η, and α, then (α, β, γ) can be expressed by a function of only w. If sinx=ξ, |x|
Since the angle is 90°, Equation (12) is: ξ−√1− ² tanδ=sinη/cosα …(12)′ If we eliminate the square root of Equation (12)′ with respect to ξ and rearrange it in order of descending powers of ξ, we get ( 1+tan ² δ)ξ ² −2・sinη／cosαξ+sin ² η
−tan ² δ/cos ² α=0…(13) Solving equation (13) for ξ yields ξcosα=sinηcos ² δ±cosηsinδ…(14).

Here, by substituting equation (14) into equation (1), we get 2cos ² α=√3｜sinηcos ² δ ₂ −sin(−η)cos ² δ ₁
±cosη(sinδ ₂ −sinδ ₁ )｜…(15) Here, sinη=1/√3, cosη=√23 as (1
5) Substituting into the equation yields the following equation.

2cos ² α=｜cos ² δ ₂ +cos ² δ ₁ ±√2(sin _{δ 2} −sin δ ₁
)
| …(16) Substitute equation (6) into equation (16).

cos ² δ=1−sin ² δ=1−cos ² (w−β)sin ² α, so 2cos ² α=|2−sin ² α{cos ² (w ₂ −β)+cos ² (w ₁
−β)}±√2sin ² α{cos(w ₂ −β)−cos(w ₁ −
β)} | …(17) Now, using the double angle formula regarding cosine, cos ² (w ₂ − β) + cos ² (w ₁ − β) = 1 + {cos2 (w ₂ −
β)−cos2(w ₁ −β)}/2 …(18) cos2(w ₂ −β)+cos2(w ₁ −β)=2cos(w ₂ +w ₁ −
2β) cos(w ₂ −w ₁ ) …(19) cos(w ₂ −β) − cos(w ₁ −β)=2sin(w ₂ +w ₁ /2
−β) sin(w ₂ −w ₁ /2)…(20) is obtained. The right sides of equations (19) and (20) are 2A and 2B, respectively.
^{Expressing this as}
| …(21) Here, |A|<1, |B|<1, |sinα|≪1, equation (21) is 2−2sin ² α=2−sin ² α−Asin ² α±2√2
Bsinα …(21)′ In equation (21)′, |A|<1, sin ² α〜0, so |sinα ₁ |≒±2√2sin(w ₂ +w ₁ /2−β) sin(w
₂ −w ₁ /2)…(22) Similarly, |sinα ₂ |≒±2√2sin(w ₄ +w ₃ /2−β)sin(
w ₄ −w ₃ /2)…(22)′ Here, from equations (22) and (22)′, solving for β yields tanβ±≒sinw ₂ −w ₁ /2sinw ₂ +w ₁ /2±sinw ₄ − w ₃ /2
sinw ₄ +w ₃ /2/sinw ₂ −w ₁ /2cosw ₂ +w ₁ /2±sinw ₄ −
w ₃ /2 cosw ₄ + w ₃ /2 (same order)...(23) If the region of β is expressed as 0°360°, then from equation (23),
Four values of β are obtained. To obtain the correct β value from these four β values, use the values of φ ₅ and φ ₆ obtained by closing the 1/4 circumference shutter 8 in Figure 1 when the rotation of φ is 180°. . In addition, the above equation (22), (2
2) For convenience, two types of values α ₁ and α ₂ are used for α in Equation ′, Equation (24-1) and Equation (24-2) described later, but theoretically α ₁ = α ₂ .

X-ray diffraction cannot distinguish between the front and back sides of a crystal, so if φ exceeds 180°, φ ₅ ′ = 180° + φ ₁ , φ ₆ ′
=
180°+φ ₂ , φ ₇ ′=180°+φ ₃ , φ ₈ ′=180°+φ ₄ . However, when measuring with the 1/4 circumference shutter 8 closed, the observed φ ₅ is either φ ₅ ' or φ ₆ ', and similarly, φ ₆ is either φ ₇ ' or φ ₈ '. Using this relationship, we can determine which of the four X-ray diffraction patterns measured at 0φ<180°, φ ₁ and φ ₂ , has a positive x angle, and similarly, φ ₃ ,
It can be determined which diffraction of φ ₄ has a positive x angle.

(φ ₄ +φ ₃ )/2−(φ ₂ +φ ₁ )/2≒90°, so
If you know which of x ₁ , x ₂ , x ₃ , and x ₄ has a positive value, which of the following four ranges is correct based on the relationship between the slopes of the two types of r ₁ r ₂ in Figure 3 It can be determined whether

(i) (w ₁ + w ₂ )/2β<(w ₃ +w ₄ )/2: x ₂
＞0, x ₃ ＞0 (ii) (w ₃ +w ₄ )/2β<(w ₁ +w ₂ )/2+
180°: x ₂ > 0, x ₄ > 0 (iii) (w ₁ + w ₂ )/2 + 180° β < (w ₃ + w ₄ )/
2 + 180°: x ₁ > 0, x ₄ > 0 (iv) (w ₃ + w ₄ )/2 + 180° β < (w ₁ + w ₂ )/
2: x ₁ >0, x ₃ >0 Furthermore, selection is made from two types of β _± according to the same order of signs in equation (23). In Figures 5 and 6, w _i , w _j
When is close to β or β+180°, |sinδ ₁ |≒|sinδ ₂ | in equation (6), and since r ₁ r ₂ = constant in Figure 6, ∠top=w _j −w _i (j >i) becomes smaller. Therefore, when the range from () to () above is found, compare the values of w ₂ −w ₁ and w ₄ −w ₃ , and if w ₂ −w ₁ < w ₄ −w ₃ , then , β _± (w ₁ + w ₂ )/2 or (w ₁ + w ₂ )/2 + 180°
β can be set to a value close to . Since β obtained from equation (23) is an approximate value, the exact β is determined next. From formula (21)′, |sinα ₁ |=2√2|sin(w ₂ +w ₁ /2−β) |sin(w ₂
−w ₁ /2)/1−cos(w ₂ −w ₁ −2β)cos(w ₂ −w ₁ )=F
₁ (β)…(24−1) |sinα ₂ |=2√2|sin(w ₄ +w ₃ /2−β) |sin(w ₄
−w ₃ /2)/1−cos(w ₄ +w ₃ −2β)cos(w ₄ −w ₃ )=F
₂ (β)…(24−2) F(β)=F ₂ (β)−F ₁ (β)…(25) Using formula (25), β obtained from formula (23) is the starting value. , refine β using Newton's method.

After finding the exact value of β in this way,
α can be found from equation (24-1) or (24-2). By squaring both sides of equation (14), ξ ² cos ² α=(sinηcos ² δ±cosηsinδ) ² = 1/3±
2√2/3sinδ±2√2/3sin ³ δ+1/3sin ⁴ δ…(
26) Now, since | ^sinα |≪1, equation ( ²⁶ ) can be written as Now that α and β have been found, from equation (28)
cosx _i and cosx _j can be determined. By substituting this value into equation (3), four types of γ values can be obtained.

Here, in Figures 3 and 6, |α| takes a small value, so γ≒γ ₁ =w ₂ +w ₁ /2−45° …(29−1) γ≒γ ₂ =w ₄ +w ₃ /2-135°...(29-1). By the way, in FIG. 6, the shorter the distance, the closer the position of ' is to the bisector of <pof. Therefore, if w ₂ −w ₁ = ε ₁ and w ₄ −w ₃ = ε ₂ , then if ε ₁ ∠ε ₂ , |γ−γ ₁ |<|γ−γ ₂ |, so equation (28) Among the four types of γ obtained from equation (3), γ ₁
The one closest to can be determined to be γ. In this way, all values of α, β, and γ are determined.

As a property of cubic crystal, (w ₄ +w ₃ )/2−
Since (w ₂ + w ₁ )/2≒90°, (24−1), (24
In equation -2), |sin(w ₂ +w ₁ /2−β)|1/√2 or |sin(w ₄ +w ₃ /2−β)|1/√2. Therefore, |sinα|2sin(w ₂ −w ₁ /2) or |sinα|2sin(w ₄ −w ₃ /2). This means that if ε ₁ = w ₂ −w ₁ and ε ₂ = w ₄ −w ₃ , then if ε ₁ > 7° or ε ₂ > 7°, then at least α > 6°, and the crystal orientation is larger than the setting. It can be unambiguously determined that it is a tilted diamond chip, and it is desirable to reject it as a defective product.

When the diamond chip is a single crystal, (w ₄ +
w ₃ )−(w ₂ +w ₁ ) takes a value close to 180°. However, there are rare diamonds in which this value is close to 60° or 120°. When these diamonds were subjected to optical microscopy and Laue X-ray diffraction photography, it was revealed that they were twin diamonds. Because twinned diamond chips are composed of multiple crystals with different orientations, the polishing process is difficult and it is desirable to reject them as defective products.

The relationship between the output of the X-ray diffraction detector and the rotation of the shank axis of these two types of diamond chips (twinned and large tilted) is as shown in FIG.

In the examples of the present invention, the crystal orientations (α, β, γ) of defective products due to twin crystals, defective products due to large inclination, and non-defective products were determined according to the flowchart shown in FIG. The operation of an embodiment of the crystal orientation measuring device according to the present invention will be described according to a flowchart. After placing the sample, irradiate the sample with X-rays and start inputting data. Measure the four w, w ₁ , w ₂ , w ₃ , w ₄ ,
If (w ₄ +w ₃ )−(w ₂ +w ₁ )>160°, it can be determined that there are no twins, so proceed to the next step. (w ₄ + w ₃ )
-(w ₂ +w ₁ ) 160°, the diamond chip is determined to be twinned and defective, and the measurement of this sample is terminated.

For those that proceed to the next step, w ₂ −w ₁ ＜
7° and w ₄ −w ₃ <7°, and if the conditions are satisfied, proceed to the next step; if not, it is determined to be defective with a large inclination, and the measurement of this sample is completed.

Next, when w exceeds 180°, close the 1/4 circumference shutter and input w ₅ and w ₆ . After completing the input,
Calculate α, β, and γ, and check for α<6° and γ<6°. Items that do not meet the conditions are determined to be defective, and the values of α, β, and γ are output.
Finish the measurement of this sample. A sample that satisfies the conditions is determined to be a good product, outputs the values of α, β, and γ, and ends the measurement of this sample.

FIG. 9 shows a block diagram of the entire crystal orientation measuring device according to the present invention. In Fig. 9, the X-rays generated from the X-ray source 1 are transmitted to the X-ray source shutter 1.
0, passing through collimator 2 and diamond chip 4
irradiate. X passed through the diamond chip
The rays are absorbed by the beam stopper 5 and the diffracted X-rays enter the detector 7. The diamond chip is φ
- It is rotated by a rotating motor 11, and an encoder 12 directly connected to the motor generates angular pulses. The angular pulse passes through an interface 13, the detector output passes through a counting circuit 14, and is input to a data processing device 15 containing a microcomputer. The output after data processing is CRT16,
It is output to the printer 17 and the data recording MT 18.

In the apparatus of the example, a M ₀ X-ray tube (M ₀ Kα = 0.7107 Å) is used as an X-ray source at 40 KV-20 mA, the distance between the X-ray source and the detector is set to 130 mm, and the intensity of diffracted X-rays I≒10 ⁵ It was operated at a count/second and φ-rotation speed of 20°/second, and it took about 20 seconds to judge whether the diamond chip was good or bad and to determine the deviation angles (α, β, γ).

According to the present invention, since the axis of rotation of the sample can be used as the only axis, the data collection time can be extremely shortened compared to conventional four-axis automatic diffractometers, etc., and the structure of the sample mounting mechanism is extremely simple. Because it can be miniaturized, the distance between the X-ray source and detector can be reduced to less than 1/4,
The effective use of X-rays has made it possible to perform high-speed scanning measurements of 20°/second. As a result, crystal orientation, which previously required more than 20 minutes, can now be measured in 20 seconds, approximately 1/60th of the time, and can now be incorporated into a mass production line as a 100% inspection device. Furthermore, since it has been made smaller, it has become easier to protect against scattered X-rays, which has improved safety.

By using the crystal orientation measuring device according to the present invention, it is possible to sort out defective diamond chips and output the deviation angles (α, β, γ) of the crystal orientation, so this data can be used in the subsequent precision polishing process. By applying this method, stabilization of polishing characteristics for each sample is promoted, and it is possible to improve throughput and yield by about 10%.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the arrangement of the main parts of the crystal orientation measuring device according to the present invention, FIG. 2 is a perspective view showing the state in which the shank shaft of the diamond chip is attached,
Figure 3 shows the crystal orientation and crystal X used in the present invention.
An explanatory diagram showing the relationship between ray diffraction vectors, Fig. 4 is a diagram showing an example of an X-ray diffraction output pattern obtained by the crystal orientation measuring device according to the present invention, and Fig. 5 shows the coordinate system of the shank axis and the diamond chip crystal axis. Figure 6 is an explanatory diagram showing the geometrical relationship between two diffracted X-rays whose rotation angle φ of the diamond chip is close to each other, and Figure 7 is an explanatory diagram showing the relationship between the diamond chip and the coordinate axes. FIG. 8 is a diagram showing an example of the output pattern of diffracted X-rays with respect to the rotation angle φ of a good diamond chip.
FIG. 9 is a flowchart for determining the inclination of the crystal axis for the settings of defective and non-defective diamond chips due to large inclination. FIG. 9 is a block diagram of the crystal orientation measuring device of the present invention. DESCRIPTION OF SYMBOLS 1...X-ray source, 2...Collimator, 3...Shank axis, 4...Diamond chip, 5...Beam stopper, 6...Semicircular slit, 7...
...X-ray detector, 8...1/4 circumference shutter, 9...
Sample mounting table/micro switch, 10...X-ray source shutter, 11...φ-rotation motor, 12...
φ-rotary encoder, 13...interface, 14...X-ray count circuit, 15...data processing device, 16...display CRT, 17...display printer, 18...data recording MT.

Claims (1)

[Claims] 1. An X-ray source that can obtain X-rays of a specific wavelength, a collimator that narrows the X-rays emitted from the X-ray source, an X-ray detector that detects only the diffracted X-rays of a specific surface index group, and the X-ray detector. An X-ray detection system with a semicircular slit installed in front of the ray detector and a shutter that closes part of the X-ray detector when necessary, and the sample crystal is placed at the midpoint between the collimator and the detector. A mechanism that allows the sample crystal to be rotated at any speed using a single rotation axis perpendicular to the narrowed X-rays, and a mechanism that rotates the crystal around the axis while irradiating the X-rays, and brushes against a specific crystal plane. a mechanism capable of measuring a rotation angle at which a bragg condition is satisfied by detecting diffracted X-rays obtained when the condition is satisfied by the X-ray detection system;
The presence or absence of twins and the tilt angle can be determined only from the four rotation angle measurements taken with the shutter open.
Furthermore, it is characterized by being equipped with a calculation mechanism that can determine the crystal orientation of the single crystal from the measured values of the four rotation angles and two rotation angles of 180 degrees or more measured with the shutter closed. crystal orientation measuring device.