JP2639675B2 - Theodolite with laser - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention is provided with a laser and can set a predetermined direction from a reference position with a laser beam, and irradiates the laser beam particularly in the darkness in a tunnel or a culvert. And a theodolite capable of determining a predetermined direction.

(Prior Art) As shown in FIG. 5, a conventional theodolite equipped with a laser includes a visual optical system including an eyepiece a, a focusing mirror b, a roof prism c, a focusing lens e, and an objective lens f, and a laser g, The laser optical system includes a prism h, a condenser lens m, a prism i, a focusing lens j, a prism k, l, and an objective lens f. A laser beam can be emitted to a target by a system.

According to the theodolite, it is possible to use it, for example, in a dark tunnel or the like, to perform excavation work in accordance with the irradiation direction of the laser beam.

(Problems to be Solved by the Invention) However, the conventional theodolite described above has the following disadvantages because the objective lens is shared by both optical systems.

When the magnification of the laser (the ratio of the diameter D of the laser light emitted from the objective lens f to the diameter d of the laser light emitted from the laser g) is increased, the spread angle (divergence angle) of the laser light emitted from the objective lens f is increased. Is small, so that the laser beam spot can be used at a small distance.
As shown in FIG. 6, since the prism 1 is large, the area (shaded area) of the objective lens f effectively used in the visual optical system is small, and the visual field is dark.

Further, since the central portion of the objective lens f is used for the laser optical system, the visual optical system can use only the other area, and the resolution is poor. Further, although a small amount of the laser light is reflected by the objective lens f and enters the visual telescope, it is difficult to use the laser light in a dark field such as in a tunnel.

An object of the present invention is to provide a conventional theodolite free of such disadvantages.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a theodolite having a laser, which emits the laser light along the optical axis of a visual optical system. A laser,
A laser optical system separate from the visual optical system, and a polarizing beam splitter disposed in front of an objective lens of the visual optical system, and linearly polarized light emitted from the linearly polarized laser and passing through the laser optical system. The laser beam is reflected by the polarization beam splitter and emitted along the optical axis of the visual optical system.

(Function) The linearly polarized laser beam emitted from the linearly polarized laser beam is guided to the polarization beam splitter by the laser optical system, reflected there, and emitted along the optical axis of the visual optical system. Since the polarizing beam splitter transmits light of the visual optical system, the collimating function of the visual optical system is not hindered even if the laser light is increased in magnification by the laser optical system. Further, the laser light is not hindered by the polarizing beam splitter and does not enter the visual telescope.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a linearly polarized laser,
Is emitted from the laser beam, is reflected by a polarizing beam splitter 8 through a reflecting prism 2, a focusing lens 3, a prism 4, a focusing lens 5, an objective lens 6, and a reflecting mirror 7 of the laser optical system, and passes through a compensating plate 9. And eyepiece 10, focusing mirror 11,
The laser beam is projected coaxially with a laser optical system including a roof prism 12, a focusing lens 13, an objective lens 14, a polarizing beam splitter 8, and a compensating plate 9.
Are supported such that the S component of the linearly polarized laser light enters the polarization beam splitter 8.

The polarization beam splitter 8 outputs the linearly polarized laser light S
The component and the P component have, for example, reflectance characteristics as shown by S and P in FIG. 4, and reflect the S component of the linearly polarized laser light of 632.8 nm, for example, and reflect the P component of the linearly polarized laser light of 632.8 nm. Component, and also transmits S and P components having a wavelength shorter than 632.8 nm.

The compensating plate 9 corrects the shift caused by the polarizing beam splitter 8, and also functions as a dustproof glass.

Incidentally, the laser optical system is designed so that the laser beam L emitted from the laser 1 passes through the prism 2 and the condenser lens 3 and is condensed in the space occupied by the roof prism 12, as shown in FIGS. Therefore, the size of the housing 15 that houses the laser optical system and the visual optical system can be reduced.

As described above, the polarizing beam splitter 8 transmits the P component of the polarized laser having a wavelength of 632.8 nm and the P and S components having a wavelength shorter than 632.8 nm, so that the visual telescope hits a target object.
The laser light scattered without the polarization component can be confirmed.

As shown in FIG. 3, a Porro prism 12A may be used instead of the roof prism 12, whereby the optical system for visual observation can be shortened and the theodolite can be made compact.

(Effects of the Invention) Since the present invention is configured as described above, it is possible to increase the magnification of the laser light emitted from the laser and thereby reduce the spread angle of the laser light. Can be used at a distance, and the resolution of the optical telescope can be made equivalent to that of a telescope dedicated to surveying instruments. In addition, since there is no stray light of the laser light to the visual telescope, there is an effect that use in a dark field in a tunnel or the like becomes easy.

[Brief description of the drawings]

FIG. 1 is a diagram of a main part of one embodiment of the present invention, FIG. 2 is a cross-sectional view of the roof prism, FIG. 3 is a diagram of a main part of another embodiment of the present invention, and FIG. Characteristic diagram of the beam splitter,
FIG. 5 is a diagram of a main part of a conventional theodolite, and FIG. 6 is an explanatory diagram of its operation. DESCRIPTION OF SYMBOLS 1 ... Linearly polarized laser, 6 ... Objective lens 8 ... Polarization beam splitter, 14 ... Objective lens

Claims (1)

(57) [Claims] 1. A theodolite comprising a laser and emitting the laser light along an optical axis of an eye optical system, a linearly polarized laser, a laser optical system separate from the eye optical system, A polarizing beam splitter disposed in front of the objective lens of the visual optical system, and reflecting the linearly polarized laser light emitted from the linearly polarized laser beam and passing through the laser optical system with the polarized beam splitter, A theodolite having a laser, which is emitted along an optical axis of an optical system.