DE2818618A1 - Slide projector with printing facility - uses instant picture film to copy projected transparency and inserts additional diffuser in light path to reduce contrast - Google Patents

Abstract

A slid projector has a printing facility. When prints ae to be made of a transparency (7) an additional diffuser (6) is moved into the light path (1, 2, 3 4) from the projection lamp (2). Visual inspection of the transparency is possible on a screen (10). The copy film material is housed in a cassette (11, 12). The diffuser (6) diminishes contrast of the slide which is too geat for the instant picture type film used.

Description

Device for projecting a transparent original image

The invention relates to a device for projecting a transparent one Original image on a projection surface and for the production of copies of the original image by bringing a light-sensitive recording medium into the image plane.

Various devices of this type are known.

First of all, the enlargers must be added to this. With these the template is projected onto a flat surface and after focusing and determining the section on a piece of light-sensitive material attached there - usually photo paper - exposed. There are also printers suitable for mass production where via a viewing beam path that is spatially or temporally separated from the copying beam path the template to be copied can be examined. Finally there is microfilm technology Back enlargers that also do both projection and copying allow a template.

All of these devices are commercial devices that for the use of special copier material with appropriate sensitivity are suitable.

However, if materials are to be used for copying which are intended for recording original scenes and are rich in contrast Slides serve as templates and - because of the light intensity - with directed light are projected, occur especially when the projection is very bright, Difficulties in the uniformity of lighting and because of the required short shutter speeds.

It is the aim of the invention to provide a projection device of the initially mentioned named genus in such a way that copies can also be made on sensitive photographic materials with it can be produced without the brilliance required for projection and Brightness is impaired.

According to the invention, this is made possible by the features according to the characterizing feature Part of the claim solved.

Details of the invention emerge from the description in which an exemplary embodiment is discussed with reference to the drawing.

In a housing G is a projection lamp 2 with a Condenser system consisting of a concave mirror 1 and two Lenses 3 is made. Furthermore, a heat protection filter 4 is arranged in the area of the lenses 3. A sector shutter 5 is used in a known manner for projecting motion pictures; for the projection of It is not necessary for still pictures and is provided by an appropriate darkening device replaced when changing slides.

Between the lighting system 1 to 4 and a projection lens 8, the transparent template 7 is arranged in a known manner in an image stage. The transparent template 7 is displayed on a screen 10 by means of the objective 8 projected.

So far the device is basically known and for example realized in screen projectors for still and moving images. It is now fundamental possible to arrange a cassette 11 instead of the screen 10, which with a corresponding photosensitive slide is sealed and photosensitive Recording material 12 contains. This means that the template 7 can be copied.

However, since the original 7 is projected very brilliantly and brightly, would be when using a photosensitive material intended for recording 12 requires a very short shutter speed. Also occur in the exposure Irregularities in the illumination of the condenser are noticeable subjective viewing of the projected image is generally overlooked.

In order to remedy both, a diffuser is provided by means of a lever 9 6th can be swiveled into the beam path between condenser and template 7. This diffuser serves to weaken the light by a few light levels and for more even illumination the template 7.

Thus, a longer shutter speed can be selected, which is the use the sector diaphragm 5 or the slide changing mechanism for exposure.

A return spring 9 a is used to pivot the diffuser 6 when the lever 9 is not pressed down by means of the handle 9 b the device described is the following: When the original 7 is projected onto The diffuser 6 is pivoted out of the projection screen 10 for visual observation. As soon as the copy carrier cassette 11 is inserted instead of the projection surface 10 is, the lever 9 on the handle 9 b is manually pressed down and the diffuser 6 pivoted into the beam path. At the same time, the shutter can then be released being controlled. When you let go of the handle 9 b, the diffuser pivots as a result the restoring force of the spring 9 a again from the beam path and the projection After the cassette 11 has been removed, it can be put back onto the rear projection screen that has been placed in its place 10 take place.

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Claims (1)

Claim device for projecting a transparent original image onto a projection surface and for making copies of the original image Bringing a light-sensitive recording medium into the image plane, thereby characterized in that it has a diffuser (6) which is used when making the copies in the beam path between the condenser (3) of the projection system and the transparent one The original image (7) can be brought and when the original image (7) is viewed on the projection surface (10) can be removed from the beam path.