JPH059683Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a composite beam splitter prism that outputs incident light beams in multiple directions.

Traditionally, for example, in a phototypesetting machine, when printing an image of a character selected from a dial onto photographic paper wrapped around a drum, the image is also projected onto the viewfinder to confirm whether it is the desired character while working. However, even if the characters to be printed can be confirmed, it is not possible to know the arrangement of the sentences that have been printed up to that point.To make this possible, the light beam from the dial side is divided into three directions. It is necessary to do so.

The present invention was developed to solve these problems, and consists of a single prism that has a semi-reflective surface that reflects a portion of the incident light at a desired rate. A composite beam splitter prism configured to split the beam is provided.

An embodiment of the present invention will be explained with reference to the drawings.
1 has the upper surface facing from the front upper edge to the rear upper edge.
The central prism piece is formed on an inclined joint surface 2 that slopes downward at an angle of 45 degrees, and its lower end surface becomes a joint surface 3 that slopes downward at an angle of 45 degrees as it moves from the lower edge of one side to the lower edge of the other side. It has been formed. Therefore, the upper and lower joint surfaces 2 and 3 are opposed to each other with a phase difference of 90 degrees in the plane direction.

4 is an upper prism piece whose front surface is formed into a semi-reflective surface 5 inclined at an angle of 45 degrees from the upper edge to the lower edge; this semi-reflective surface 5 is integrated with the upper joint surface 2 of the central prism piece 1; The rear surface is formed into a total reflection surface 6 which is inclined forward at an angle of 45 degrees from one side edge to the other side edge.

7 is a right triangular lower prism piece, which forms a semi-reflective surface 8 with a surface inclined at an angle of 45 degrees;
The semi-reflective surface 8 is integrally bonded to the lower joint surface 3 of the central prism piece 1.

Incidentally, the semi-reflective surface 5 of the upper prism piece 4 is configured to reflect, for example, 400 to 500 nm of visible light with a wavelength of 380 to 700 nm.
It is formed on a surface that allows 90 to 80% of the light rays with a wavelength of 500 to 700 nm to pass through, and 80 to 70% of the light rays with a wavelength of 500 to 700 nm, and reflects the remaining light rays, and the lower semi-reflective surface 6 is formed from the upper semi-reflective surface 5. It is formed on a surface that transmits about 90% of the reflected light rays and reflects the remaining 10%.

As shown in FIG. 3, the composite beam splitter prism A constructed in this way is placed between the collimating lens 9 and the shutter 10 in a phototypesetting machine, with its total reflection surface 6 facing the shutter 10 side and its upper semi-reflection surface 5 being placed as a finder. 11, lower semi-reflective surface 8
They are arranged so as to respectively face the image pickup device 12 of the CRT.

Now, the light beam from the halogen tungsten light source 13 with a wavelength of 350 to 750 nm is reflected from the mirror 14 to the condenser lens 15, the reflective mirror 16, the dustproof glass 17, the dial 18, the magnifying/reducing lens system (main lens system) 19, and the deformable lens system. 20, central prism piece 1 of compound prism A via collimating lens 9
irradiate. In this state, when a desired character is selected from the dial 18 according to the aperture 21, most of the light ray a incident on the central prism piece 1 passes through the upper semi-reflective surface 5 and is angled at right angles by the total reflective surface 6. The emitted light beam b is reflected in the direction of the shutter 10.
While traveling straight to the side, the light beam reflected by the upper semi-reflective surface 5 reaches the lower semi-reflective surface 8, and this lower semi-reflective surface 8
The output light beam c that has passed through is introduced into the viewfinder 11 and projects an image of the letter, and the reflected light beam d is introduced into the imager 12 of the CRT and projects the same image on a portion of the cathode ray tube.

Therefore, when the shutter 10 is turned off, the total reflection surface 6
The image of the light ray b reflected by the moving lens system 22
The image is printed on the photographic paper wrapped around the drum 23 through the image. Furthermore, all the characters printed on the photographic paper are displayed on the cathode ray tube of the imager 12.

In the above embodiment, the compound prism was used in a phototypesetting machine, but it can also be used in any optical device that needs to split the incident light beam into multiple directions. Reflective surfaces 5, 8
The light reflectance can be changed as appropriate depending on the type of reflective thin film.

As described above, the present invention has a central prism piece formed on the upper and lower joint surfaces 2 and 3, the upper and lower surfaces of which are inclined at an angle of 45 degrees perpendicular to the horizontal plane, and which face each other with a phase of 90 degrees in the plane direction. 1, and an upper prism having a front end surface formed as a semi-reflective surface 5 integrally joined to the upper joint surface 2, and a rear end surface formed as a total reflection surface 6 inclined horizontally with respect to the vertical surface. piece 4 and the inclined upper surface of the central prism piece 1.
Since this relates to a composite beam splitter prism characterized by comprising a lower prism piece 7 formed on a semi-reflective surface 8 integrally joined to the lower member joining surface 3, the beam incident on the central prism piece 1 is A plurality of light beams can be emitted in a desired direction via the upper and lower semi-reflective surfaces 5 and 8, and can be advantageously used in optical equipment that needs to separately project the same image.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a perspective view thereof, FIG. 2 is an exploded perspective view, and FIG. 3 is an explanatory view when the invention is used in a phototypesetting machine. 1...Central prism piece, 2, 3...Joint surface, 4
... Upper prism piece, 7... Lower prism piece,
5, 8... Semi-reflective surface, 6... Totally reflective surface.

Claims (1)

[Scope of utility model registration request] A central prism piece 1 formed on upper and lower joint surfaces 2 and 3 whose upper and lower surfaces are inclined at an angle of 45 degrees perpendicularly to the horizontal plane and which face each other with a phase of 90 degrees in the plane direction; A total reflection surface 6 formed as a semi-reflection surface 5 integrally joined to the joint surface 2 and whose rear end surface is inclined in the horizontal direction with respect to the vertical surface.
The composite beam is characterized by comprising an upper prism piece 4 formed with a slanted upper surface and a lower prism piece 7 formed with a semi-reflective surface 8 whose slanted upper surface is integrally joined to the lower joint surface 3 of the central prism piece 1. Pritzter Prism.