JP2970223B2 - Optical scanner for confocal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a confocal optical scanner used for a confocal microscope or the like, and more particularly to a pinhole capable of reducing the influence of eccentricity during rotation of a pinhole substrate constituting the confocal optical scanner. It is about placement.

[0002]

2. Description of the Related Art FIG. 7 is a block diagram showing an example of a confocal microscope using a confocal optical scanner, and FIG. 8 is a conventional example of a pinhole substrate used for a confocal optical scanner. 7 and 8, a light emitted from a light source (not shown) passes through a deflector 1a and a beam splitter 2, and a plurality of pinholes 32 are spirally formed on a substrate 31. 3 is irradiated. Of the irradiation light, the pinhole substrate 3
The light that has passed through some of the many pinholes 32 arranged in a spiral shape is condensed on a sample 6 via a quarter-wave plate 4 and an objective lens 5. The reflected light from the sample 6 passes through the same optical path and is condensed on one of the pinholes 32 of the pinhole substrate 3, passes through the pinhole 32, and emits the beam splitter 2 and the deflector 1b. Through the eyepiece 7 and the sample 6
Image can be captured with the eyes. In this apparatus, the pinhole substrate 3 is rotated at a constant speed by a motor 8.
The focused light spot on the sample 6 is scanned by the movement of the pinhole 32 accompanying the rotation of the pinhole substrate 3.

[0003]

However, in the confocal optical scanner shown in the above prior art, the center of the pattern of the plurality of pinholes 32 spirally formed on the pinhole substrate 3 and the pinhole substrate 3 Center of rotation (motor 8
Deviated from the center), when one screen is constituted by one scan, stripes are generated on the screen.

The reason for the occurrence of these stripes is that, as shown in FIG. 9A, when a track (circle) rotating with an eccentricity e is observed in a window, the x coordinate of the observation point A is As shown in the figure, the cycloid (approximately si
n), and this amplitude changes by 2e at 180 °. Here, a case is considered where measurement is performed so that scanning of one screen is constituted by 90 °. Fig. 9 (a) and (b)
, When the scanning is started from the point B, the radius increases by e until the point A is reached. Therefore, in one-screen scanning at 90 °, point B ′ of the pinhole pitch should be originally scanned, but A having a radius larger than the point B ′ by the eccentricity e is used.
Pass through a point. Therefore, the area between the points B 'and A is excessively scanned, and the screen becomes white. Conversely, when the point is between the point B 'and the point C, the scanning is insufficient and the screen becomes black. Actually, since the scanning is performed by the arc, the stripe generated due to the eccentricity has a shape as shown in FIG.

In order to eliminate these stripes, the amount of eccentricity must be made sufficiently small. In addition, even if the eccentricity is large, by forming one screen with two or more scans, the stripes generated due to the eccentricity are reduced, but the S / N is deteriorated. Conventionally, it has been very difficult to adjust the amount of eccentricity, and it has not been possible to naturally separate and replace the pinhole board and the motor.

The present invention has been made in view of the above-mentioned problems of the prior art, and provides a confocal optical scanner having a pinhole substrate having a pinhole arrangement in which stripes are unlikely to occur even in a state of large eccentricity. It is intended to do so. The term “screen” used in this specification,
“Article” and “virtual truck” have the following meanings, respectively.
The taste. "Screen": A sample obtained based on multiple pinholes
A screen on which an image is projected or displayed . "Art": A series of pinhole rows related to scanning one screen
(Or pinhole group). "Virtual track": Pinhole where pinhole is placed
An area on the substrate where the pinhole substrate is
Pinholes extending in the radial direction divided into multiple pieces at regular intervals
Refers to the placement area. In FIG. 1, the virtual tracks are radially arranged.
Are indicated by chain lines. Attached to these virtual trucks
A numbered, referred to as the virtual track No or track No
You.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a configuration of the present invention is to rotate a pinhole substrate on which a plurality of pinholes are formed, and apply irradiation light passing through the pinhole substrate to a sample. In the confocal optical scanner for scanning with respect to, the plurality of pinholes are provided on the pinhole substrate.
Placed and associated on each virtual track
A series of pinholes as a row of pinholes
There are multiple rows of pinholes in the radial direction of the pinhole board.
Each pinhole of those multiple pinhole rows arranged
Have different radii at the center, and
If the holes are sequentially numbered in the direction of rotation
In the scanning order, the inner diameter side is odd-numbered and the outer diameter side is even-numbered.
Or the inner diameter side is even-numbered and the outer diameter side is odd-numbered.
As well as the innermost circumference of each row of pinhole rows
The outermost pinhole is separated from the virtual track by one track
Characterized by being formed so as to be placed at
I do.

[0008]

[ Function ] A plurality of pin holes in the radial direction of the pinhole substrate
Arrange rows of files. Each pin of the multiple pinhole row
Each hole has a different radius at the center, and
For the pinhole of the ridge, the inside diameter side is odd
The outer diameter side is an even number or the inner diameter side is an even number
It is formed so that the radial side is odd-numbered and
The innermost and outermost pinholes in the hole row are virtual toes.
Position the rack so that it is one track away from the rack.
You. Radial position due to eccentricity as the rotation of the pinhole substrate advances
Becomes large. Rotation angle in conventional pinhole row
The amount of deviation monotonically increased in proportion to the
The width of the fringes in the portion scanned at the end of the row also increased.
In the present invention, the innermost and outermost pins of each pinhole row are arranged.
Hole is only one track away from the virtual track
Therefore, the width of the stripe is much smaller than in the past.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. Since the description of the confocal optical scanner is the same as that of the conventional one, only the pinhole arrangement will be described below. FIG. 1 is a specific example showing a pinhole arrangement of a pinhole substrate constituting a confocal optical scanner of the present invention. The feature of this pinhole arrangement is that one screen is scanned by a plurality of pinhole rows, and the radius of the center position of all the pinholes constituting the plurality of pinhole rows on one screen is reduced. It is characterized by being arranged differently. Specifically, as shown in FIG. 1, first, a radial virtual track is assumed on a substrate, and a pinhole is arranged at an arbitrary radius on the virtual track.
It is configured by scanning of N pinholes. Rotation direction (virtual track N ₀ ): i = 1, 2, ──, N Radial direction (from inside): j ₁ , j ₂ , ──, j _N (N = 7 in FIG. 1). Also,
In the radial direction (j direction), let the radius of each pinhole be r ₁ , r ₂ ,
Ｒ, r _N. Note that the diameter increment s is constant between all pinholes. That is, r _{j + 1} = r _j + s, where r ₁ = r ₀ + s.

With such a pinhole arrangement, conventionally, a pinhole row (a spiral shape) whose radius monotonically increases.
In the case of scanning in the direction of rotation, as shown in FIG. 2A, the deviation δ (= g × i) due to the eccentricity depends on the rotation direction (track No.).
Gap between adjacent pinholes due to eccentricity in proportion to i
(Displacement from the original position in the radial direction)
In the last pinhole (i = N), deviation due to eccentricity
δ becomes g × N, and the point where the scanning of rN should be performed is eccentrically pulled back to scan rN ′. Here, as shown in FIG.
Is twice as p2 (= 2 · p1), two screens constitute one screen. Then, the uppermost stage is scanned by the N / 2-th scan, but the deviation due to the eccentricity at this time is gN / 2
, Which is less than that of the single article. However, since the scanning pitch is doubled, the image quality becomes rough. At this time, as shown in FIG. 2C, if the center radius of the pinhole of the second row is shifted entirely by p1 from the first row, the scanning will start exactly between the first row and the image quality is It is equivalent to that of Article 1, and the effect of eccentricity is reduced. The number of the articles is not limited to two, but may be three or more. If the number of monotonically increasing rows is brought to the limit, the number of rows becomes N. That is, since the radius of adjacent pinholes can be determined independently, a pattern that minimizes the effect of eccentricity can be selected, and a circular pattern has a radial equiangular pitch. This is the pinhole arrangement shown in the above specific example.

In the pinhole arrangement shown in FIG. 1, the pinholes sequentially numbered in the rotation angle direction are odd-numbered on the inner diameter side, even-numbered on the outer diameter side, and have a radius on the inner diameter side in the scanning order. They are arranged under the following conditions so that they increase monotonically and decrease monotonically on the outer diameter side. (N is an odd number, N
/ 2 is rounded up. (1) In the case of 1 ≦ j ≦ N / 2 (half of the inner diameter side), the radius at which the pinhole is arranged: r _j = r ₀ + s × j── The track number at which the pinhole is arranged: i = 2j -1─
─ (2) When N / 2 <j ≦ N (half of the outer diameter side) Radius where pinhole is arranged: r _j = r ₀ + s × j── Track number where pinhole is arranged: i = N- {2 (j
−N / 2) -1} ──

When the pinhole board having such a pinhole arrangement is mounted on a motor or the like and rotated, the pinhole board shown in FIG.
The scanning is performed in the order shown in FIG. FIG. 3 shows a case where N = 34. Here, consider a case where an eccentricity e causes scanning of r 'different from the true radius r. Generally, in order to measure a plurality of screens by one rotation of the pinhole substrate (in the example of FIG. 8 shown in the section of the prior art, 16 lines = 16 images /
The amount of deviation of the radial position (or the gap between adjacent pinholes) due to eccentricity in one screen monotonously increases or decreases with respect to the angle. Assuming that the gap between the adjacent pinholes is g [μm / pinhole], the deviation of the radial position of the j-th pinhole from the inner diameter side is r _j ′ = r _j + i × g──.

In the conventional case, the displacement of the last pinhole r _N
δ is g × N. In contrast, in the present invention, the last pin
The hole r _N moves from the first pinhole as shown in FIG.
The last pinhole r
The shift δ of _N is g × 1 (= g). Compared to conventional one
And the width of the stripe is 1 / N that of the conventional case.
N is greatly reduced. Here, the light and dark unevenness of the middle part
Is considered. In the arrangement of the pinholes shown in FIG. 3, the scanning order (the order of the i) of the pinholes (the order of the j) from the inside to the outer peripheral direction is shifted by two (in the conventional example shown in FIG. 8, one by one). Is shifted). For example, i = 1,2,2
3,. . . In the lower column, j = 1, 3,
5 ,. . . , The upper row is j = 32, 30, 28,. . .
It is. That is, as shown in FIG. 4, the amount δ deviated from the true radius r by the eccentricity e is 2 g in all cases. In addition,
In the present invention, the change of i with respect to the change of j is as follows.
Swell. On the inner circumference side, from the equation, ij + 1-ij = {2 (j + 1) -1}-(2j-1) = 2 , and on the outer circumference side, ij + 1-ij = N- ＝ 2 ((j + 1) -N / 2) -1}-[N- {2 (j-N / 2) -1}] =-2. This means that the inner circumference shifts by 2 g and scans a wider area than when there is no eccentricity (therefore, as an image,
Darker ), the outer circumference is shifted by -2g and there is no eccentricity
Scan a smaller area (so the image will not be brighter)
). Pertaining to uneven brightness caused by eccentricity e
The shift amount δ ′ is 4 g. In addition, in the conventional thing, g
Scan a wider area than when there is no eccentricity by shifting, or
Do you scan a smaller area than when there is no eccentricity shifted by g
In areas other than stripes, the entire area becomes darker or brighter.
Was one of them.

Here, for example, one screen is constituted by scanning of N = 34 pinholes, and a gap due to eccentricity is formed.
Assuming that g is 1 μm, the conventional one is
The deviation δ (width of the stripe) is 34 μm, but the deviation δ in the present invention is
(The stripe width) is 1 μm. It should be noted that in the present invention,
The deviation δ ′ is 4 g = 4 μm (regardless of N).
), But the difference in brightness on one screen can be ignored
It is only about. As mentioned above, the stripe width of 34 μm is 1
μm is more characteristic,
This is also a remarkable effect of the invention.

In the above embodiment, in the pinholes sequentially numbered in the rotation angle direction, the inner diameter side is odd-numbered, the outer diameter side is even-numbered, and the radius monotonically increases on the inner diameter side in the scanning order. However, the pinholes are arranged so as to monotonically decrease on the outer diameter side. (1) In the order of scanning, the inner diameter side is odd-numbered, the outer diameter side is even-numbered, and the radius decreases monotonically on the inner diameter side. It increases monotonically on the outer diameter side. (2) In the order of scanning, the inner diameter side is even-numbered, the outer diameter side is odd-numbered, and the radius monotonically increases on the inner diameter side and decreases monotonically on the outer diameter side. (3) In the scanning order, the inner diameter side is even-numbered, the outer diameter side is odd-numbered, and the radius monotonically decreases on the inner diameter side and increases monotonically on the outer diameter side. Pinholes can be arranged as shown, and the same effect is exhibited
can do. In addition, the pattern shown in FIG.
The innermost and outermost pinholes that make up the screen are virtual
Is located one track away from the
Similar effects can be exerted.

Further, the eccentricity is not limited to the single-mountain arrangement shown in the above embodiment, but to the double-mountain arrangement as shown in FIG.
The shift amount δ ′ related to the uneven brightness caused by the unevenness is shown in FIG.
As shown in FIG.

In short, a plurality of pinholes for scanning one screen
Of the center position of the
The inner diameter side of the pinhole row is odd-numbered and the outer diameter side is even-numbered.
Or make the inner diameter side an even number and the outer diameter side an odd number
The innermost and outermost pinholes are virtual tracks.
To be positioned one track apart
By this, the width of the stripe generated due to eccentricity can be reduced.
Wear.

Next, when one screen is scanned, if a plurality of pinholes are used at the same time instead of one pinhole as shown in the above embodiment, the measurement can be speeded up. For example, as shown in FIG. 6, pinholes are radially arranged, and the same angle θ _i (i = 1, 2,.
─, N _m ) are considered to place two pinholes separated by a pitch p. In this case, the radius of the pinhole at the adjacent angle θ _{i + 1} is at a position shifted by the scanning pitch s.
Assuming these as j ₁ , j ₂ , ──, j _N , the number N of pinholes required to compose one screen is N _m = p / s [number]. In a multi-pinhole structure, whatever value the field of view of the magnitude Q is always when the scan angle direction by N _m is performed, one screen measurements is completed. This is a single pinhole (one pinhole on the same angle θ)
In the configuration, when the scanning takes N _m times time. Therefore, p [μm] in the radial direction and N _m [number] in the circumferential direction are 1
It can be considered that one block is configured. In the case of a multi-pinhole configuration, this block may be treated as one screen, and the measurement can be speeded up. Even in such a multi-pinhole configuration, it is possible to implement together with the pinhole arrangement of the configuration shown in the above embodiment, and it is possible to reduce the width of the stripe generated due to eccentricity, Measurement can be speeded up.

Next, when the pinholes are arranged at an equiangular pitch as in the above embodiment, that is, when the pinholes are arranged on the radial virtual track,
For example, even if the scanning order is helical,
Since the interval between the virtual tracks is wider than the inner circumference, the amount of light (density) on the outer circumference is smaller than that on the inner circumference, causing uneven brightness during light scanning. As a pinhole arrangement free from uneven brightness during light scanning, there is Japanese Patent Application No. 03-286112 “Confocal Optical Scanner” by the present applicant. Although the description in the drawings is omitted for this already-filed application, the virtual track is considered to be a band having a constant width,
It is arranged to be rolled up inside. In this case, the outer circumference of the virtual track is smaller than that in which the pinholes are arranged at a regular pitch. If the multi-pinhole rows on the virtual track are arranged at the same pitch of the pitch p, the distance between the pinholes is constant regardless of the diameter.
In particular, assuming that the pitch p is equal to the width of the virtual track, the density is equivalent to that of a square arrangement. Since the curvature of the spiral is generally sufficiently large, the spiral is almost straight within the range of the pitch p, and the influence of the bending can be ignored. As a result, an arrangement can be made in which unevenness in brightness between the inner and outer peripheries of the pinhole substrate is eliminated. Even in such a case, it is possible to implement the pinhole arrangement having the configuration as described in the above embodiment together, and it is possible to reduce the width of the stripe generated due to the eccentricity and to reduce the width of the pinhole substrate. It is also possible to perform optical scanning on the inner and outer circumferences without uneven brightness.

Next, although not shown in the drawings, the pinhole substrate is arranged at the focal position, and the plurality of pinholes arranged on the pinhole substrate are as follows.
By using a confocal optical scanner including a condensing substrate having a plurality of microlenses arranged so as to be at the same position with respect to the optical axis, the light use efficiency can be further improved.

[0021]

As described above in detail with the embodiments, according to the present invention, even when the eccentricity is large, the confocal light having the pinhole substrate having the pinhole arrangement in which the stripe is hardly generated. The scanner can be realized, the eccentricity can be easily adjusted, and the pinhole board and the motor can be separated and exchanged.

[Brief description of the drawings]

FIG. 1 is a specific example showing a pinhole arrangement of a pinhole substrate constituting a confocal optical scanner of the present invention.

FIG. 2 is a diagram illustrating a pinhole used in the confocal optical scanner of the present invention.
FIG. 4 is a diagram for explaining a method of arranging pin holes on a metal substrate.

FIG. 3 is a diagram showing the order of scanning when the pinhole pattern of FIG. 1 is rotated.

FIG. 4 is a diagram for explaining a reduction in a shift amount due to eccentricity according to the present invention.

FIG. 5 is a diagram illustrating a scanning order and a shift amount due to eccentricity according to another embodiment of the present invention.

FIG. 6 is a diagram showing a pinhole arrangement according to another embodiment of the present invention.

FIG. 7 is a configuration diagram illustrating an example of a confocal microscope using a confocal optical scanner.

FIG. 8 shows a conventional example of a pinhole substrate used for a confocal optical scanner.

FIG. 9 is a diagram illustrating the generation of fringes due to eccentricity.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-302215 (JP, A) JP-A-4-330412 (JP, A) JP-A-4-347801 (JP, A) 503493 (JP, A) Table 5-5-235235 (JP, A) Appl. Phys. Lett, vol. 53 (8) (22 August 1988), p. 716-718; Q. Xiao et al. : "Real-time confocal scanning optical microscopic" SCANNING, 7 [2] (1985), p. 97-108 JOURNAL OF THE OP TICAL SOCIALY OF A MERICA, 58 [5] (1968), pp. 661-664 (58) Fields investigated (Int. Cl. ⁶ , DB name) G02B 21/00

Claims (4)

(57) [Claims] 1. A confocal optical scanner for rotating a pinhole substrate on which a plurality of pinholes are formed, and scanning a sample with irradiation light passing through the pinhole substrate. Hall, associated respectively disposed Rutotomoni before Symbol pinhole on the virtual track on the substrate
A series of pinholes is formed as a single row of pinholes.
Multiple pinhole rows are arranged in the radial direction of the hole substrate.
The pinholes of the multiple pinhole rows are
The radius of the center position differs from each other, and
Scanning when numbers are sequentially assigned to the rotation direction
In this order, the inner diameter side is odd-numbered and the outer diameter side is even-numbered or inner.
It is formed so that the radial side is even and the outer diameter is odd.
And the innermost and outermost circumferences of each row of pinholes
Pinhole is one track away from the virtual track
An optical scanner for confocal , characterized in that it is formed so as to be arranged at a position . 2. The confocal optical scanner according to claim 1, wherein the plurality of pinhole rows are located at the center positions of the pinholes.
The radius of the installation increases monotonically on the inner diameter side and decreases monotonically on the outer diameter side.
Or decrease monotonically on the inner diameter side and decrease monotonically on the outer diameter side.
An optical scanner for confocal, wherein the optical scanner is arranged so as to increase in tone . 3. The confocal optical scanner according to claim 1, wherein the plurality of pinhole rows are arranged on the pinhole substrate.
Arranged at the same pitch on radial virtual conformal tracks
Or a confocal optical scanner arranged on a spiral virtual track . 4. The confocal optical scanner according to claim 1, wherein said pinhole substrate is disposed at a focal position thereof, and said plurality of pinholes are formed on said pinhole substrate. A confocal optical scanner, comprising: a light-collecting substrate having a plurality of microlenses arranged and formed at the same position with respect to the optical axis.