GB2364135A

GB2364135A - Liquid crystal display or transparency overhead projector

Info

Publication number: GB2364135A
Application number: GB0015550A
Authority: GB
Inventors: Ching-Chen Chen
Original assignee: Rever Computer Inc
Current assignee: Rever Computer Inc
Priority date: 2000-06-27
Filing date: 2000-06-27
Publication date: 2002-01-16
Anticipated expiration: 2020-06-27
Also published as: GB2364135B; GB0015550D0

Abstract

A multifunction projector comprises a reflector 2, a lamp 3, a condenser lens 4, two plastic Fresenel lens 5 inside a shell 1 from bottom to top. A support arm 6 is mounted on one side of the shell with lens 7 and adjustable mirror 8 on the top of it. Light emits from the lamp and may project the image and data on a transparency (15, Fig 3) Fresnel lens to the screen 9 on the front side of the device. The projector also comprises a circuit board 10 that transfers analog signal into digital signal in order to drive a liquid crystal display panel 11 inside the shell; a signal input terminal 12 thereon extends and is fixed onto one side of the shell. A moveable liquid crystal display panel 11 is arranged above or between the two Fresnel lens and connected to foregoing circuit board. When the device being used, the liquid crystal display panel is connected to the computer and the running program in the computer is projected through the panel to be displayed on a screen or the device just works as a traditional overhead projector for displaying data on transparencies (15, Fig 3).

Description

2364135 MULTIFUNCTION PROJECTOR t The invention relates to a multifunction

projector, more particularly to an overhead projector which is either connected to computers by means of cables or is used with traditional transparencies to display images on screen.

BACKGROUND OF THE INVENTION

A traditional overhead projector projects images and data on transparencies onto the screen based on the principle of Fresnel lens and optics The device has been applied to education, training, briefing, conference etc However, after being used for decades, such static and monochrome device of presentation can't meet the needs of users due to the prevalence of computers Therefore, electronic projection system such as liquid crystal display ( LCD) projector is getting popular in these years.

Although liquid crystal display projector connected with computers has a great many of advantages like colorful and animated images, lightweight, and portable Yet it also has following drawbacks:

a) cost expensive Owing to the use of special optic engine such as small-size liquid crystal display or DLP (digital light processor), the cost of such projectors is so high that they are not as generally accepted as overhead projectors In addition, it requires the use of a computer and the necessary technical interfaces to work properly.

b) lack of brightness In general, the luminance of the overhead projector is from 2000 to 7500 lumens (the unit of illumination) but the range of luminance of general liquid crystal display projectors is from 300 to 2000 lumens By the way, the liquid crystal display projector with 2000 lumens of light is worth more than 10000 dollars, much more than the price of the overhead projector with the same brightness, range from 250 to 300.

c) without the use of transparency films In practice, users don't always need to run and edit the show by computer software and project through liquid crystal display projectors during some brief presentation.

Some modifications of illustrations or graphs that even can't be made by computers are easily drawn by hands on transparencies Such kind of convenience, quickness, and popularity is what liquid crystal display projectors can't reach.

SUMMARY OF THE INVENTION

Therefore, it is an object of the present invention to provide a multifunction projector having both the advantages of traditional overhead projectors and modem liquid crystal display projectors The present invention is not only quite economic but also well accepted by users.

In order to achieve the foregoing object, the present invention comprising a concave reflector with a lamp therein, a condenser lens two pieces of plastic Fresnel lens, in this sequence from the bottom to the top inside a shell, a support arm disposed on lateral side of the shell, a projection lens and an adjustable mirror mounted on top of the support arm Light from the lamp passes through the condenser lens as well as Fresnel lens and then is converged by the projection lens, reflected by the mirror and finally arrives the screen The device is characterized in:

A circuit board of liquid crystal display panel that transfers analog signals to digital signals in order to drive the panel is mounted on the bottom of the foregoing shell: a signal input terminal is arranged on one side of the shell and a slot for accommodating a moveable liquid crystal display panel is disposed at another side of the shell The liquid crystal display panel is arranged between or above the two Fresnel lens and is connected to the above-mentioned circuit board by means of cables.

With the above structure, the device is connected to PC or Mac computers by means of cables to transmit the graphs or data therein onto the liquid crystal display panel accommodating thereof When the lamp shines through the condenser lens, Fresnel lens, and transparent liquid crystal display panel, images make their way through the projection lens, being reflected by the mirror and displayed on a screen in front of the projector On the other hand, when the liquid crystal display panel is separated from the Fresnel lens, the device is used with traditional transparencies as traditional overhead projector Therefore, by using only one set of the present invention, different kind of presentation material such as images on transparent films and programs in computers can be-applied to a briefing Not only the cost is much lower than the conventional liquid crystal display projector but the application of the present invention is much broader.

The above object, features and advantages of the present invention will become apparent from the following description when taken in conjunction with the accompanying drawings in which a preferred embodiment of the present invention is shown by way of illustrative example.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG 1 shows a front view of the present invention; FIG 2 is an embodiment of the present invention connected to computers; FIG 3 is another embodiment of the present invention used with transparencies; FIG 4 is a cross-sectional view of one embodiment of the present invention; FIG 5 is a cross-sectional view of another embodiment of the present invention; FIG 6 is a front view of one embodiment of the present invention showing the support arm folded into the shell 1 DETAILED DESCRIPTION OF THE PREFERRED

EMBODIMENTS Refer to FIG 4, FIGS, the present invention comprising a concave reflector 2, a lamp 3 on the recession of the reflector 2, a condenser lens 4, two plastic Fresnel lens in above sequence from the bottom to the top inside a shell 1, a support arm 6 on lateral side of the shell 1, a projection lens 7 and an adjustable mirror 8 disposed on the top of the support arm 6 Light emitting from the lamp 3 passes through the condenser lens 4, Fresnel lens 5 and converged by the projection lens 7 and then reflected by the mirror 8 so that the images above Fresnel lens 5 are projected on a screen 9 in front of the present invention.

The present invention is characterized in:

a circuit board 10 that transfers analog signal to digital signal in order to drive the liquid crystal display panel 11 is mounted inside the shell 1 mentioned above A signal input terminal 12 extends outwards from the circuit board 10 of liquid crystal display panel 11 is fixed on one lateral side of the shell 1 In addition, a slot 13 for accommodating a moveable liquid crystal display panel 11 ( a transparent plate) is disposed on another lateral side of the shell 1 The liquid crystal display panel 11 is either arranged between two Fresnel lens 5 (as shown in FIG 4) or above two closed Fresnel lens 5 (as shown in FIG 5) and connected to the circuit board 10 for accepting signal from computers or other video sources The liquid crystal display panel 11 can be either inserted into the slot 13 or drawn outwards (as shown in FIG 3) The lamp 3 is powered by a power supply of metal complex as light source for projection.

With reference to FIG 6, when the device is not in use, the support arm 6 can be folded into the shell 1 In this embodiment, the slot 13 is disposed on the front side of the shell 1.

With the above structure, refer to FIG 2, the signal input terminal 12 on lateral side of the shell 1 is connected to a computer 14 (a notebook shown in FIG 2) by means of cables and the information run in the computer 14 is transmitted to the liquid crystal display panel 11 inserted inside the slot 13 and is showed on the screen of the panel 11 Light from the lamp 3 emits through condenser lens 4, two plastic Fresnel lens 5 and passes the transparent liquid crystal display panel 11 Any programs showed thereon are projected through the projection lens 7 and reflected by the mirror 8, then arrives a large-scale screen in front of the projector.

In FIG 3, the liquid crystal display panel 11 is drawn outside and left the top of the Fresnel lens 5 Traditional transparencies are disposed onto the top of the stage (above the Fresnel lens 5) and the device works as a traditional overhead projector.

Therefore, users only need to prepare the present invention that is used either as a traditional overhead projector used with transparent films or as an advanced liquid crystal display projector that connects with computers or other video sources The present invention is easy to operate, broadly applied and less expensive than traditional liquid crystal display projector thus it will be generally accepted.

Although certain preferred embodiments have been shown and described, it should be understood that many changes and modifications may be made thereto without departing from the scope of the invention.

Claims

1 a multifunction projector comprising:

a concave reflector, a lamp on the recession of said reflector, a condenser lens, two pieces of plastic Fresnel lens, all arranged in this sequence from the bottom to the top inside a shell, a support arm disposed on lateral side of said shell, a projection lens and an a adjustable mirror mounted on top of said support arm; light from the lamp passes through said condenser lens and said Fresnel lens, then converged by said projection lens, reflected by said mirror and finally arrives a screen; the device is characterized in:

a circuit board of liquid crystal display panel that transfers analog signals to digital signals in order to drive said panel is mounted into said shell with a signal input terminal thereon extends outside one lateral side of said shell; a slot for accommodating a moveable liquid crystal display panel is disposed at another lateral side of said shell, wherein said liquid crystal display panel is arranged between said two Fresnel lens and is connected to said circuit board by means of cables.

2 A device as claimed in claim 1, wherein said moveable liquid crystal display panel is arranged above said two Fresnel lens.

3 A multifunction projector substantially as herein described with reference to and as illustrated in the accompany drawings.

Amendments to the claims have been filed as follows REV 1457 GB CLAIMS 1 A multifunction projector comprising:

a concave reflector, a lamp on the recession of said reflector, a condenser lens, two pieces of plastic Fresnel lens, all arranged in this sequence from the bottom to the top inside a shell, a support arm disposed on a lateral side of said shell, a projection lens and an adjustable mirror mounted on top of said support arm; in use, light from the lamp passing through said condenserlens and said Fresnel lens, being then converged by said projection lens, reflected by said mirror to a screen; characterised by:

a circuit board of a liquid crystal display panel which transfers analog signals to digital signals in order to drive said panel is mounted into said shell, a signal input terminal extending from one lateral side of said shell; a slot for accommodating a movable liquid crystal display panel is disposed at another lateral side of said shell, wherein said liquid crystal display panel is positionedxab-p^ at least one Fresnel lens and is connected to said circuit board by means of cables.

2 A multifunction projector as claimed in claim 1, in which the moveable liquid crystal display panel is positioned above the two Fresnel lenses.

3 A multifunction projector as claimed in claim 1, in which the moveable liquid crystal display is positioned between the two Fresnel lenses.

4 A multifunction projector substantially as herein described with reference to and as illustrated in the accompanying drawings.

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