JPH058499Y2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application The present invention relates to an adjustment mechanism for optically adjusting the slit position of a scanning spectrometer installed in an emission spectrometer or the like.

(b) Prior art and its problems In general, a Zernitana-type emission spectrometer is equipped with a scanning spectrometer. In this type of scanning spectrometer, the dispersive element is driven at high speed by a pulse motor, so the angular feed becomes somewhat rough, so the exit slit must be finely adjusted to match the target wavelength. Therefore, the exit slit is slidably attached to a slit stand.

Furthermore, in this spectrometer, it is necessary to set the mechanical center point of the exit slit in advance in order to adjust the entire optical system. Therefore, conventionally, as shown in FIG. 4, a slit table T provided with an exit slit S
Limit switches L1 and Lr are provided on the left and right sides of the slit table T, and the slit table T is moved left and right by a pulse motor (not shown).
1. Measure the distance until contact with Lr,
Based on the results, the mechanical center point of the exit slit S was set. For example, if the slit table T is located at approximately equal distances from the left and right limit switches L1, Lr, first move the slit table T to the left until it contacts the limit switch L1, and measure the number of pulses during that time. Next, the slit table T is moved rightward from that position until it comes into contact with the limit switch Lr, and the number of pulses during that time is measured. Then, since the center point can be determined mechanically from the number of pulses while the slit table T moves left and right, the slit table T is subsequently moved leftward to the position of the center point.

However, even with such a mechanism, setting the center point requires a large amount of movement of the slit table (approximately one round trip in the above example).
Setting the center point takes time. Moreover, since the slit table and the limit switch are in mechanical contact, the position of the limit switch may shift over time.

The present invention was developed in view of these circumstances, and is a method for setting the mechanical center point of the exit slit in a short time and with high precision when adjusting the optical system of a scanning spectrometer. The purpose is to make it possible.

(c) Means for solving the problem In order to achieve the above-mentioned object, the present invention has a light-shielding plate attached to a slit stand that slidably supports the exit slit of the spectrometer, and the light-shielding plate has the above-mentioned structure. A light-emitting unit that forms a reference edge at a position on the optical path of the dispersed light passing through the exit slit and detects the presence or absence of the reference edge at a mechanical center point for optical adjustment of the exit slit; a photo sensor having the light-emitting unit; are arranged to constitute the adjustment mechanism of the spectrometer.

(d) Effect When the light receiving part of the photo sensor is detecting light, move the slit table in a certain direction (for example, to the left).
move it to When the reference edge of the light-shielding plate reaches a position on the optical path of the photo sensor, the light from the light-emitting part is blocked by the light-shielding plate and the light-receiving part no longer detects the light, so the movement of the slit table is stopped at that point.

Conversely, if the light from the light emitting part of the photo sensor is blocked by the light shielding plate, the light is not detected by the light receiving part, so the slit table is moved in the opposite direction (to the right). When the reference edge of the light-shielding plate reaches a position on the optical path of the photo sensor, the light receiving section detects light, and at that point, the movement of the slit table is stopped. In this way, the exit slit is set directly at the center point.

(E) Embodiments The present invention will be described in detail below based on embodiments shown in the drawings.

FIG. 1 is a perspective view of an adjustment mechanism of a spectrometer according to an embodiment of the present invention, and FIG. 2 is a side view showing a part of a photo sensor and a light shielding plate. The adjustment mechanism 1 of the spectrometer in this embodiment has an exit slit 2 of the spectrometer.
A light shielding plate 6 is attached to a slit table 4 that slidably supports the slit table. This light shielding plate 6 has a part cut out so that the dispersed light 8 passing through the exit slit 2 can be cut out.
A reference edge 12 is formed at a position on the optical path 10 .

On the other hand, a photo sensor 14 for detecting the presence or absence of the reference edge 12 is disposed at the mechanical center point of the exit slit 2 for optical adjustment (this is uniquely determined by the mechanical positional relationship of the spectrometer). . The photo sensor 14 includes a light emitting section 16 for emitting and receiving light and a light receiving section 18 that are arranged facing each other, and in this example, a photo interrupter is applied.

Therefore, in the adjustment mechanism 1 of this spectrometer, the light shielding plate 6 is now in the position shown by the two-dot chain line in FIG. If so, the slit table 4 is moved to the left in the figure by a pulse motor (not shown). The reference edge 12 of the light shielding plate 6 is the third
As shown by the solid line in the figure, when the light from the light emitting section 16 reaches a position on the optical path of the photo sensor 14, the light from the light emitting section 16 is blocked by the light shielding plate 6 and the light receiving section 18 no longer detects the light. A stop signal is given to the pulse motor to stop the movement of the slit table 4. The reference edge 12 is preset to lie on the optical path 10, so that the exit slit 2 is mechanically centered.

Contrary to the above, the light emitting part 16 of the photo sensor 14
When the light shielding plate 6 is interposed between the light receiving part 18 and the light receiving part 18, the light from the light emitting part 16 is blocked by the light shielding plate 6, so that the light is not detected by the light receiving part 18. In this case, the slit table 4 is moved to the right in FIG. When the reference edge 12 of the light shielding plate 6 reaches a position on the optical path of the photo sensor 14, the light is no longer blocked by the light shielding plate 6, and the light receiving unit 18 detects the light. At that point, the movement of the slit table 4 is immediately stopped. In this way, the exit slit 2 will be set directly at the mechanical center point.

(f) Effect As described above, according to the present invention, the amount of movement of the slit table is small, and the center point can be detected without contact, so when adjusting the optical system of a scanning spectrometer, the exit Effects such as being able to set the mechanical center point of the slit within a short time and with high precision are exhibited.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the present invention, in which FIG. 1 is a perspective view of the adjustment mechanism of the spectrometer, FIG. 2 is a side view showing a part of the light shielding plate of the photo sensor, and FIG. A plan view for explaining the positional relationship of a light shielding plate with respect to a photo sensor, and FIG. 4 is a schematic plan view showing an adjustment mechanism of a conventional spectrometer. 1... Spectrometer adjustment mechanism, 2... Exit slit, 4... Slit stand, 6... Light shielding plate, 10...
Optical path, 12... Reference edge, 14... Photo sensor,
16... Light emitting section, 18... Light emitting section.

Claims (1)

[Scope of utility model registration request] A light shielding plate is attached to a slit base that slidably supports the exit slit of the spectrometer, and a reference edge is formed on the light shielding plate at a position on the optical path of the dispersed light passing through the exit slit. An adjustment mechanism for a spectrometer, characterized in that a photo sensor having a light emitting part and a light receiving part for detecting the presence or absence of the reference edge is disposed at a mechanical center point for optical adjustment.