Projector having a projector lens part and a cover part

A thin type projector is disclosed. The thin type projector according to present invention includes a panel part slidingly mounted at the front surface of the housing to open and close the projection lens part selectively. The thin type projector may further include a speaker part installed at the front surface of a housing, the speaker part converting an audio input signal into sound. When the panel part is separated, a lamp as a light source is exposed to the front of the housing. As a result, a user can replace the lamp with a new one conveniently.

TECHNICAL FIELD

The present invention relates to a thin type projector. More specifically, the present invention relates to a thin type projector which includes a panel part slidingly mounted on a front surface thereof, selectively opening and closing a projection lens part for projecting images.

BACKGROUND ART

Projectors are apparatuses which project enlarged images to a screen via a projection lens once image input signals of various display devices.

Projectors may be categorized into a PRT (CRT) type, liquid crystal display (LCD) type and digital light processing (DLP) type. Recently, LCD type projectors have been popular because of an advantage of connection with PCs.

According to the LCD type projector, light which is generated from a light source lamp passes a transparent LCD panel to display images on a front screen.

FIG. 1is a perspective view of a conventional projector. The projector shown inFIG. 1includes a projection lens part10′ provided on a front surface of a wide box shaped housing20such that generated images may be projected via the projection lens part.

An optical system of the projector includes a lightening part, a micro device and a projection lens part. The lightening part generates and emits light. The micro device realizes three dimensional images by using the light. The projection lens projects the images. The micro device may be a transparent LCD panel to receive an image input signal from an outside and to display images, if the projector is a LCD type.

The projector100′ shown inFIG. 1is wide box-shaped with a large horizontal area. As a result, the above projector100′ should be installed on an auxiliary table or on the ceiling. A thin type projector has been introduced with an improvement of the optical system and the thin type projector means a thin box-shaped projector.

FIG. 2illustrates an embodiment of the thin type projector. This thin type projector100′ includes a projection lens part10′ provided at a front surface of an upright box-shaped housing20′, with an exposed lens.

As shown inFIG. 2, this thin type projector may a stand type which uses a stand50′ or a wall-mount type. Even if this thin projector is a stand type, this thin projector has a small horizontal area than the conventional projector shown inFIG. 1. If it is a wall mount type, this thin type projector is simpler to install than the conventional projector installed in the ceiling.

The thin projector receives an image input signal of various kinds display devices and projects enlarged images to a screen via the projection lens. Here, the various display devices may provide a sound input signal, rather than the image signal. The display devices supply the image signal to a TV, DVD player, portable multimedia player (PMP) or PC. An auxiliary sound device should be provided if it is necessary to amplify a small capacity of a speaker of the display device, for example, a lap top computer and if a portable display device without a speaker is connected with the thin type projector.

While the conventional projector turned on, images are projected from the projection lens part. While the conventional projector is turned off, a separate private usage cover is mounted to the projection lens to protect the projection lens part from dust, scratches or shocks.

DISCLOSURE OF INVENTION

Technical Problem

However, the private usage cover of the projection lens part may happen to be lost and the protection of the projection lens might not be reliable.

Furthermore, if the light source lamp should be replaced, the whole housing is separated to separate the light source lamp, which is inconvenient.

A still further, if the thin type projector shown inFIG. 2is wall-mounted, all eyes will be on the wall-mounted thin type projector. As a result, it is necessary to consider a design balance of the projector.

Technical Solution

To solve the problems, a thin type projector includes a upright box-shaped housing; a lightening part mounted at a front surface of the housing to expose a lamp light source to the front surface, the lamp light source generating and emitting light; a micro device converting a display input signal received from an outside into a video signal to be projected; a projection lens part mounted at the front surface of the housing to expose a lens unit to the front surface of the housing, the lens unit converting the image, converted from the light of the lightening part by the micro device, into a projection light to enlarge and project the projection light; and a panel part slidingly mounted at the front surface of the housing to open and close the projection lens part selectively.

The thin type projector may further include a speaker part installed at the front surface of the housing, the speaker part being exposable, wherein the panel part selectively opens or closes the projection lens part or the speaker part when the panel part sliding.

The speaker part may be provided in plural, the plurality of the speakers being spaced apart a predetermined distance in a horizontal direction.

The panel part may open and close the projection lens part and the speaker part simultaneously, if the panel part is sliding.

The panel part may open and close either of the projection lens part and the speaker part before the other.

A predetermined portion of the panel part is projected at the front surface of the housing and the panel part may be operated by a pinion gear operated by a motor mounted in the housing and a rack provided at a rear surface of the panel part, the rack engaged with the pinion.

A guide groove may be provided at either of the rear surface of the panel part and the front surface of the housing to guide the sliding motion of the panel part, and a guide protrusion ay be provided at the other to be inserted in the guide groove.

An upward motion prevention switch and a downward motion prevention switch may be pressed to turn off the motor when the panel part is sliding, the upward and downward motion prevention switches being projected from the front surface of the housing by a spring.

The sliding motion range of the panel part may be limited by a prevention protrusion provided at one of the front surface of the housing and the rear surface of the panel part and a limiter provided at the other of the front surface of the housing and the rear surface of the panel part.

The panel part may include a front plate exposed forward, the front panel being replaceable; and a liner defining a rear surface of the panel part.

The front plate may be made of transparent plastic or glass such that a decorative material is inserted between the front plate and the liner.

The panel part may be separable from the housing.

The lamp light source of the lightening part can be separated, when the panel part is separated from the housing.

The panel part may be configured of a display device to display an image identical to the image realized in the micro device.

The speaker part provided at the front surface of the housing may be positioned higher than the projection lens part, and if only an audio signal is supplied from an outside, the panel part is sliding downward to an opening position opening only the speaker part and if a video signal is inputted from the outside, the panel part is sliding downward farther to an opening position for opening the projection lens part below the speaker part.

Advantageous Effects

The present invention has following advantageous effects.

According to a thin type projector of the present invention, a projection lens part is protected from outside stimulus and an auxiliary audio output device is not necessary because an audio input signal is outputted via a speaker part.

Furthermore, it is convenient to replace a light source lamp which is a consumption part with a new one.

A still further, users' various aesthetic demands may be satisfied because a decorative material can be inserted in a panel part or a front plate can be replaceable.

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 3is a perspective view of a thin type projector according to an exemplary embodiment.

According to the exemplary embodiment shown inFIG. 3, a thin type projector100includes a projection lens part10and a panel part30. The projection lens part10is mounted at a front surface of a housing20which is vertically upright box-shaped, with a lens unit exposed outside via the front surface of the housing to project images generated from a micro device. The panel part30is slidingly mounted on the front surface of the housing to selectively open and close the projection lens part10.

FIG. 3presents that the panel part30of the thin type projector sliding moves upward and downward. If the panel part30sliding moves to selectively close the projection lens part10, the motion is not limited to the upward-and-downward direction and it may be a right-and-left direction.

A lightening part (not shown) is provided in the housing to generate light from the light source lamp and a micro device (not shown) is provided in the housing to receive the light and to realizing images.

If the projection lens part10projects images, the panel part30is sliding downward to open the projection lens part10. If the image is projected completely, the panel part30sliding upward to close the projection lens part10. The motion direction and motion distance of the panel part10may be determined according to the position of the panel part30.

The thin type projector100can receive and convert a sound input signal into sound to project the sound toward the front surface of the housing. For that, the thin type projector100further includes a speaker part40exposed to the front surface of the housing.

An auxiliary sound device should be provided in the thin type projector100, if the display devices transmit a sound input signal as well as an image input signal. If the speaker is mounted on the front surface of the housing20, the speaker may replace the auxiliary sound device.

Even in case of the display device having a sound signal output part, the speaker part40may be usable as the sound output device in a lap top PC with a small capacity of a speaker, which should be amplified, or a portable display device only with an earphone terminal, no speaker.

FIG. 4is an exploded perspective view of an example of the panel part30. The panel part30includes a replaceable front plate32exposed to its front surface and a liner38defining its rear surface. Here, the panel part30may be a trim-kit type.

It is preferable that the front plate32may be fabricated in various shapes and colors to be selectable according to various demands of users.

Because of the front plate with the various kinds of shapes and colors, various production lines may be possible.

In addition, the front plate32is replaceable afterward such that changing user demands of beauty may be satisfied.

The front plate32is configured of transparent plastic or glass and a decorative material may be inserted between the front plate32and the liner38. At this time, the decorative material may be a photograph or picture.

The front plate32and the liner38shown inFIG. 4may be fastened to a panel frame34by a bolt and e.g.

The panel part30is mounted on the front surface of the housing20and the panel part30is slidable upward and downward to selectively open and close the projection lens part10and the speaker part40, if it is provided.

Guide grooves and corresponding guide protrusions may be formed at a rear surface and the front surface of the housing20, respectively, to guide the sliding motion. According to the embodiment ofFIG. 4, the guide grooves341and381may be provided at the panel part30. Specifically, the guide grooves341and381are provided at the panel frame34and the liner38, respectively, such that a single protrusion is inserted in the guide grooves341and381. Alternatively, the positions of the guide groove and the guide protrusion (not shown) may be vice versa, which may create the same performance as the above positions of them.

FIG. 5is a diagram illustrating the front surface of the housing20according to the thin type projector according to the exemplary embodiment. As shown inFIG. 5, guide protrusions281and282are formed at the front surface of the housing20. Then, the guide protrusions281and282are inserted in the above guide grooves341and381to guide the sliding motion of the panel part30.

The guide protrusion corresponding to a numeral reference281is inserted in the guide grooves341and381to guide the sliding motion of the panel part30and to prevent the panel part30from being separated from the housing20.

The guide protrusion corresponding to a numeral reference282is inserted in the guide groove formed at only the liner38. the guide protrusions and the guide grooves shown inFIGS. 4 and 5are just examples and they may be changeable in various ways only if they are used as means for allowing the panel part30mounted on the front surface of the housing20and preventing the panel part30from being separated from the housing20.

A lightening part60is provided in the housing20and a lamp (not shown) used as a light source is exposed via the lightening part60. According to the conventional projector shown inFIGS. 1 and 2, the lightening part is positioned in the housing to generate and emit light. To replace the lamp, the housing should be destructed. It is expected to replace the lamp with a new one regularly, because the lamp used as a light source of the lightening part has limited usage time. However, it is not simple for a user to destruct the housing and to replace the lamp.

The light source part60of the thin type protector according to the exemplary embodiment has access to the lamp from the front surface of the housing20. That is, although a light source lamp of the light source part60is accessible from the front surface of the housing20, the sliding motion range of the panel part30is limited not to expose the lamp light source outside during the normal usage of the thin type projector.

If the panel part30is separable from the housing20when replacing the lamp with a new one, the lamp light source is accessible to replace the lamp without the destruction of the housing20.

As shown inFIG. 5, a prevention protrusion284is provided at the front surface of the panel part30to prevent the panel part30from sliding over the normal sliding motion range. A function and work of the prevention protrusion284will be described in reference toFIG. 6.

FIG. 6is a perspective view of a switch and an enlarged view of a rear surface of the switch.

If a forward-and-backward movable switch385provided at both lower ends of the liner38of the panel part30closes an opening hole384provided at a lower edge of the liner38, the switch385to prevent the panel part30from moving upward over the allowable sliding motion range.

A power of the motor is turned off by an upward motion prevention switch86, which will be described later, and a rotation of a pinion gear89is stopped to prevent the upward motion of the panel part30. At this time, the prevention switch385prevents the additional upward motion of the panel part30to complement problems of power cut-off control failure and e.g.

However, the prevention switch385moves backward if the panel part30is separated from the housing, such that the panel part30may move upward over a position of closing the projection lens part10.

FIG. 7is an exploded perspective view illustrating the housing and the panel part. Lower ends of the guide grooves381,382and341are cut out partially (not shown specifically in the drawings) such that the guide protrusions281and282having a cross section of a ‘’ shape may be separated from the guide grooves. Although not shown in the drawings, an external input terminal or button type control signal input part may be provided at a side or lower surface of a rear cover90composing the housing20.

In the above process, the panel part30is separated from the housing20and the user can replace the lamp of the light source part60.

FIG. 8illustrates an operation part80provided in the housing20to slidingly move the panel part30.

The rotational force of a motor81of the operation part80is transmitted to the front surface of the housing20and some of the rotational force is transmitted to the projected pinion gear89, and then the pinion gear89is coupled to a rack389provided at a rear surface of the liner38and the rotational force of the pinion gear89is transmitted to the rack389, only to sliding move the panel part30upward and downward.

The operation part80includes a gear box83which converts a rotation speed of the motor81rotated by electric currents.

The rotational force of the motor81is transmitted by a worm gear811and thus load generated by an abnormal operation of the panel part is not transmitted to the motor81.

If a direction of the electric currents supplied to the motor81is changed, it is possible to move the panel part30to an opening position from a closing position of the projection lens part10or vice versa.

If the motor81is configured of a direct current (DC) motor, the change of the electric current direction may enable the change of the rotation direction of the motor.

A sound or display signal of the display device and an on-signal of the projector may be used as an electric current supply signal for operating the motor81.

If a display, sound or on-signal is transmitted from the outside, with the panel part30of the projector according to the exemplary embodiment being placed at a closing position of the projection lens part10and the speaker40, a display, sound or on-signal is used as an electric current supply signal of the motor81and the electric current is supplied to the motor81. Because of the operation of the motor81, the panel part30is sliding upward to an opening position of the projection lens part10.

In reverse, if the display or sound signal transmitted from the outside is cut off or an off-signal is transmitted, with the panel part30being placed at the opening position, the cut-off display or sound signal or the off-signal is used as a signal of electric current supply and electric currents are supplied to the motor81in the opposite direction. As a result, the panel part30is sliding to the opening position of the projection lens part10.

As mentioned above, the signal of the electric current supply may be the display signal, sound signal, which are transmitted from the display device, or on-signal. A signal of cut off the electric currents is transmitted from a first switch86and a second switch88which are projected from the housing.

The first switch86stops the upward motion of the panel part30and the second switch88stops the downward motion of the panel part30. The first and second switches86and88are not pressed, while they are inserted in first and second grooves formed at a rear surface of the liner38shown inFIG. 7, respectively. Once the normal motion of the panel part30is complete, the first and second switches86and88are out of the first and second grooves386and388. The switches out of the grooves, respectively, are pressed. If the switches are pressed, it is identified that an electric current cut off signal is generated.

FIGS. 9 and 10illustrate a thin type projector according to other embodiments, respectively. according to the above embodiment, the thin type projector includes the panel part30capable of selectively closing the projection lens part10and the speaker part40is arranged in parallel with the projection lens part10to be opened or closed together with the projection lens part10according to the sliding motion of the panel part30.

However, if only the sound signal is inputted without the display signal received from an external input terminal, the projection lens part10does not have to be opened and only the speaker part40has to be opened. Then, if the panel part30opens only the speaker part, the thin type projector100according to the present invention may have an independent function of sound output.

As a result, if the display signal or sound signal is not received from the input terminal, a control part controlling each configuration of the thin type projector may controls the motor such that the panel part30closes both the projection lens10and the speaker part40to protect the projection lens10and the speaker part40from foreign matters.

In addition, if the display signal is transmitted from the input terminal, the control part may control the motor such that the projection lens part10is exposed as shown inFIG. 9. According to the embodiment shown inFIG. 9, the speaker part40is positioned higher than the projection lens part10and the speaker part40is also exposed only with the display signal transmitted from the input terminal.

That is, the reason why the panel part30is opened gradually under the control of the control part is that the projection lens part10or the speaker part40which is not used often is not exposed for a long time. As a result, only the used configuration is exposed according to the position or input signal of the projection lens part10or the speaker part40and the control part control the motor to determine the sliding motion position of the panel part30.

According to the thin type projector shown inFIGS. 9 and 10, two speaker parts40are provided on an upper portion of the front surface of the housing20and the projection lens part10is provided at a lower portion, compared with the speaker parts40.

If the display signal is inputted, the panel part30is sliding to the opening position to open both the speaker parts40and the projection lens part10from the closing position to close the whole portion of the housing20(see,FIG. 9). If only the sound signal is inputted, the panel part30is sliding to the opening position to open only the speaker parts40as shown inFIG. 10, because the projection lens part10does not have to be opened.

In contrast to the embodiment ofFIGS. 9 and 10, it is possible to exchange the positions of the projection lens part10and the speaker part40at the front surface of the housing40. Even if then, the sliding motion position of the panel part30may be determined according to the kind of the input signal received from the outside.

FIG. 11illustrates a thin type projector according to a still further embodiment. According to the thin type projector shown inFIG. 11, the panel part sliding upward and downward to close the projection lens part10and the speaker part40may be a flat panel display (FPD)30′. As mentioned above, the embodiment shown inFIG. 11presents that the thin type projector is installed on a stand50and it may be wall-mounted.

If the panel part is the flat panel display device30′, there may be following advantages. First, the display signal may be displayed via the FPD device30′ the display signal is projected via the projection lens10simultaneously.

In this case, to the FPD device30′ is transmitted via a cable the signal which is identical to the display signal received from the external display device to be supplied to the micro device. For that, a through hole (not shown) is formed at the front surface of the housing20and the cable pass the trough hole to supply the display signal and the on-signal to the FPD device30′.

This can give the thin type projector according to the present invention an advantage in that the user can identify the image projected from the projector lens part. Also, if the display device is configured of a LCD device having a touch screen open frame or a LCD device having a touch screen sensor, the user can control a computer connected as the external input device via the FPD device30′. That is, the user can identify the image output of the computer and the projected image simultaneously.

According to the embodiment of the thin type projector shown inFIG. 11, the external input is displayed via the FPL device30′ with the panel part30being at the closing position to close the overall the housing20. As a result, the thin type projector according to this embodiment may be used as a monitor of a computer, e.g.

It is preferable that the display signal input transmitted from the external device is selectively outputted via the projection lens part10or the FPD device30′ and via both of them. This selection may maximize utilization of the thin type projector.

To embody the above function, the thin type projector may include a HDMI terminal, a RCA terminal, an S-video terminal, an analog RGB (D-sub) terminal and DVI terminals. In addition, the thin type projector includes a sound signal input terminal to receive a sound signal.

Except the input terminals such as HDMI terminal which transmits the display signal together with the sound signal, the display input terminals such as Analog RGB (D-sub) which transmits the display signal not together with the sound signal may be used as display input terminal. If then, an auxiliary sound signal cable is connected with the display device and the sound input terminal of the thin type projector such that the sound signal is outputted via the speaker part40.

Moreover, if the thin type projector includes a DVD player, a reproduction circuit having a multimedia reproduction program and external memory receiving terminals such as USB terminal, the thin type projector can directly play multimedia files inputted from the memory receiving terminal. As a result, the thin type projector may be utilized as an independent multimedia device.