JP2885100B2 - Infrared reflective objective - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infrared reflection objective used in the total reflection measurement method (ATR method) for analyzing a sample by irradiating infrared light to a prism on which the sample is adhered and totally reflecting the sample.

[0002]

2. Description of the Related Art Light is incident on a prism made of a high-refractive-index material that transmits infrared light at an incident angle greater than a critical angle (the angle at which total reflection occurs), and the light totally reflected at the boundary between the prism and the sample is measured. Then, infrared spectrum information can be obtained. Such a total reflection measurement method (ATR method) is effective for obtaining infrared spectrum information on the surface of a soft rubber, plastic film, or a substance having a flat surface. When infrared light is incident on the sample from the prism, the depth h into which the infrared light penetrates is expressed by the following equation. h = λ / 2π (sins ² θ−n ₂₁ ² ) ^1/2 where θ: incident angle n ₂₁ : refractive index of sample / refractive index of prism λ: wavelength Therefore, if the incident angle θ is reduced, the depth h into which the infrared rays can be penetrated can be increased, and the infrared information inside can be obtained accordingly.

FIG. 5 is a diagram showing a configuration of a conventionally known ATR objective mirror. That is, an infrared light source (not shown)
The infrared light transmitted through the aperture 15 passes through the aperture 15 and is reflected by the mirrors 5 and 11 to enter the prism 3 on which the sample is adhered, and the further reflected infrared light is reflected by the mirrors 10 and 5 Then, it enters a detector (not shown), and its infrared spectrum information is obtained.

[0004]

As described above, the depth at which infrared light penetrates into a sample depends on the incident angle, and spectral information at different depths can be obtained by changing the incident angle. However, with the conventional ATR objective, the angle of incidence is always constant and cannot be changed. Therefore, a person in charge of analyzing the sample can easily change the angle of incidence by an infrared reflecting objective. There is a strong voice that demands. The present invention has been made in view of such a problem, and an infrared reflecting objective mirror capable of easily changing the depth of penetration of infrared light from a prism to a sample and obtaining different information of the same substance. The purpose is to provide.

[0005]

In other words, in order to solve the above-mentioned problems, the present invention provides an infrared reflecting objective means for moving a prism up and down with respect to a sample surface, and interlocking with the up and down movement of the prism. It is characterized by comprising a mirror for changing the angle of the infrared light incident on the prism and the angle of the infrared light receiving mirror from the prism, and making the angle of incidence of the infrared light on the prism variable. Alternatively, an infrared reflecting objective mirror is fixed at a lower end with a prism for adhering the sample, and a projection is provided at an intermediate portion so as to be movable up and down. A mirror inserted so as to be able to move up and down, a holding tool whose entire periphery is loosely fitted into a projection formed in the middle of the fixing bar, and one end pivotally attached to the holding tool so as to be rotatable; Are provided with a connecting rod through which a beam whose both ends are rotatably connected to the end of the mirror is inserted, and both ends which are connected to the ends of the beam at the fixed portion of the frame. Sliding fit into the groove and free the other end.
And a mirror slidably fitted in the other groove provided in the fixing portion of the drum.

[0006]

The operation when the infrared reflecting objective is used as the above means will be described with reference to the reference numerals in the accompanying drawings. First, when the fixed bar 1 is rotated, the fixed bar 1 moves in the vertical direction.
The connecting rods 7, 7 pivotally attached to the fixed rod 1 swing at both ends while rotating, and furthermore, a mirror 10 pivotally attached to both ends of the beam 8 inserted through the connecting rods 7, 7. Slide in grooves 12 and 13, respectively. At this time, the prism 3 and the mirror 5 are relatively separated or approach.

The infrared light incident on the mirror 5 is a mirror.
The light is reflected by 11 and enters the prism 3. The reflected light from the prism 3 is reflected by the mirrors 10 and 5 and reaches the detector. When the fixing rod 1 on which the prism 3 is fixed is rotated, both ends of the mirrors 10 and 11 slide and move along the grooves 12 and 13, respectively. That is, the connecting rods 7 connected to the fixing rod 1 (holding tool 6) and the mirrors 10 and 11 push and pull the mirrors 10 and 11, respectively. Then, as shown in FIG. 4, the mirrors 10 and 11 move as shown by the two-dot chain line, and the prism 3 also moves as shown by the two-dot chain line. Thus, the light incident on the prism 3 can be changed from θ to θ ′. Therefore, it is possible to change the depth of infrared rays penetrating into the sample adhered to the prism 3.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of a link mechanism of the infrared reflecting objective mirror of the present invention, and FIG.
FIG. A fixing rod 1 is arranged at the center of the infrared reflecting objective mirror, and a prism 3 for adhering the sample is fixed and attached to a lower end of the fixing rod 1 by a holder 2, and an upper end is provided with a male screw 1a. The frame 4 is screwed into a female screw provided on a part of the fixing portion. The fixing rod 1 has an intermediate portion inserted through a central portion of a mirror 5 installed on a fixing portion such as the frame 4 or the like.

A projection 1b is formed at a part of the fixing bar 1 slightly above the middle of the fixing bar 1, and the entire periphery of the projection 1b is loosely fitted into the holder 6.
FIG. 3 shows an enlarged view thereof. Therefore, the fixing bar 1 can be moved up and down together with the holder 6 by rotating. Reference numeral 7 denotes a connecting rod, one end of which is rotatably mounted on a holder 6 fitted in the fixing rod 1.

As shown in FIG. 2, a long beam 8 is inserted into the other end of the connecting rod 7, and both ends of the beam 8 are slightly bent to form a mirror 10 (the other end). Mira-1
1 is provided symmetrically with respect to the mirror 10 with respect to the fixed rod 1 and will be described with reference to the mirror 10).
And pivotably attached. A roller 9 is provided on the projection bar 10a of the mirror 10 so as to be smoothly slidably fitted in a groove 12 provided in a fixed portion such as a frame. Further, the other end of the mirror 10 is provided with another groove 1 provided in a fixed portion such as a frame by a roller (not shown) through a roller.
3 is slidable.

The link mechanism of the infrared reflecting objective mirror according to the present invention has the above-described structure. When the fixing rod 1 is rotated, the fixing rod 1 engages the male screw portion 1a with the female screw of the frame 4. So move up and down. The connecting rods 7, 7 pivotally attached to the fixing rod 1 (holding tool 6) swing while their both ends rotate, and furthermore, the both ends of the beam 8 pivotally attached to the connecting rods 7, 7 Both ends of the pivoted mirrors 10, 11 slide in grooves 12 and 13, respectively. Further, at this time, the prism 3 and the mirror 5 are relatively separated or approached.

By rotating the fixed rod 1 and moving it up and down, infrared rays can be made incident on the prism 3 and reflected by the prism 3 as follows. That is, as shown in FIGS. 1 and 4, the infrared rays are reflected by the mirrors 5 and 11 and enter the prism 3. The reflected light from the prism 3 is Mira-10
Then, the light is reflected by the light source 5 and reaches a detector (not shown). Mira
10 and 11 move up and down when the fixed rod 1 to which the prism 3 is fixed is rotated. That is, the connecting rods 7 connected to the fixing rod 1 (holding tool 6) and the mirrors 10 and 11 push and pull the mirrors 10 and 11, respectively. By the operation of this link mechanism, the mirrors 10 and 11 move as shown by the two-dot chain line in FIG. 4, and the prism 3 also moves as shown by the two-dot chain line. Thus, the light incident on the prism 3 can be changed from θ to θ ′. Therefore, it is possible to change the depth of infrared rays penetrating into the sample adhered to the prism 3.

[0013]

As described above in detail, according to the infrared reflecting objective mirror of the present invention, the incident angle of the infrared ray to be incident on the prism can be changed in various ways, so that the depth at which the infrared ray penetrates the sample from the prism is changed. be able to.
Therefore, it is possible to obtain infrared information at portions having different depths from the surface of the sample toward the inside, for example, when the degree of deterioration of the polymer changes from the surface toward the inside.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a link mechanism of an infrared reflecting objective mirror of the present invention.

FIG. 2 is a view taken in the direction of the arrow Q in FIG. 1;

FIG. 3 is a partially enlarged view showing a connection state of a fixing rod, a holder, and a connection rod.

FIG. 4 is a view showing the operation of a mirror when the fixing rod is moved up and down in the link mechanism of the infrared reflecting objective mirror of the present invention.

FIG. 5 is a diagram showing a schematic configuration of a conventional infrared reflecting objective mirror.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixing rod 3 Prism 4 Frame 5 Mirror 6 Holder 7 Connecting rod 8 Beam 10, 11 Mirror 12, 13 Groove

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁶ , DB name) G01N 21/00-21/01 G01N 21/17-21/61 G02B 7/198 G02B 26/08

Claims (2)

(57) [Claims] 1. A means for moving a prism up and down with respect to a sample surface, and a means for changing an angle between a mirror for incident infrared light on the prism and an infrared light receiving mirror from the prism in conjunction with the vertical movement of the prism. And a variable angle of incidence of infrared light to the prism. 2. A fixed rod which is fixed to a lower end of the prism and which is attached to the sample and which can be vertically moved by providing a projection at an intermediate part; and a fixed rod which is mounted on a fixed part of the frame and which can be vertically moved. A holder which is loosely fitted around the entire periphery into a projection formed in the middle of the fixing rod; one end is pivotally attached to the holder and is rotatably connected to the other end. Is a connecting rod through which a beam whose both ends are pivotally connected to the end of a mirror is inserted, and both ends which are pivotally connected to the ends of said beam are slid into grooves provided in a fixed portion of the frame. An infrared reflecting objective mirror comprising: a mirror movably inserted; and a mirror slidably inserted at the other end into the other groove provided in the frame fixing portion.