JP2003280098A - Cap for projection lens and projector equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cap for a projection lens with which stability in the handling of a projector is enhanced and an image mute can be substitutionally used by basically intercepting projected light from a projection lens in addition to the protection of the projection lens, while causing leaked light in a direction where effect exerted on an operator or a presenter present on a projection side is reduced so as to discriminate the presence/no presence of the projected light. <P>SOLUTION: The cap for the projection lens 10 is equipped with a lens counter surface 11 arranged to be opposed to the lens surface of the projection lens 3 and an outer peripheral surface 12 present around the surface 11 and fit on the edge part of the lens 3. Then, the surface 11 is set as a light shielding surface, and the surface 12 is made a translucent surface or provided with a hole. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection lens cap and a projector including the cap.

[0002]

2. Description of the Related Art A projector for projecting an image using a projection lens is usually provided with a cap for protecting the projection lens from external damage. Conventionally, the cap is
In order to protect the lens and also have a function of preventing light from leaking to the outside of the projection lens, it is usually manufactured from black plastic or the like.

[0003]

However, in the conventional cap that completely blocks light, it is possible to determine whether light is projected from the projection lens at first glance while it is attached to the projection lens. Can not. Therefore, there is a possibility that a small child accidentally removes the cap from the projection lens even though the light is being projected, and the light may unexpectedly damage the eyes.

Further, the projector has a so-called image mute function for forcibly turning the displayed image into black. However, when the brightness of the illumination light increases, the illumination light leaks from the black display screen toward the explainer on the projection side. For example, at the time of a presentation, the presenter may not be able to fully exert the effect of the presentation because the presenter becomes dazzled by the leaked light and the reaction of the audience becomes difficult to see. Therefore, in such a case, the lamp of the light source is OF
It is also conceivable to eliminate the light from the projection lens to the explainer on the projection side after F. However, in recent high-intensity projectors, an ultra-high pressure mercury lamp is often used as the lamp, which also has the following problems. That is, since the ultra-high pressure mercury lamp emits light by evaporating the mercury enclosed in the arc tube, it takes time for the mercury to warm up and completely evaporate, and it takes 1 minute or more to enter a stable state. In addition, since the outer wall temperature of the arc tube is kept at a high temperature of about 600 ° C. and the mercury vapor pressure is high while the ultra-high pressure mercury lamp is lit, even if the lamp is once turned off, the temperature and internal pressure of the arc tube do not immediately drop. Even if a high-frequency high voltage is applied in such a state, it is difficult for electrons to fly from the cathode to the anode and discharge is not started, so that instantaneous relighting of the lamp is impossible. Then, it takes several minutes for the mercury to return to a liquid state and be ready for relighting. For this reason, switching the projection screen to display / non-display by turning the lamp on / off is unsuitable in view of the user's usage environment because the waiting time becomes long. Therefore, as another alternative to the image mute, it is conceivable to forcibly shield the projection surface of the projection lens by using the protective cap.

The present invention has been made in view of the above problems, and in addition to protecting the projection lens, it basically blocks the projection light from the projection lens, while the operator or explainer on the projection side. A projection lens that enhances the safety of handling the projector by making it possible to determine the presence or absence of projected light by producing leaked light in a direction that has little effect on (presenter), and that can also be used as an alternative to image mute. Cap,
And it aims at providing the projector provided with it.

[0006]

In order to solve the above problems, the present invention adopts the following configurations.

A projection lens cap having a lens facing surface arranged to face the lens surface of the projection lens, and an outer peripheral surface around the lens facing surface and fitted to the tip of the projection lens. The lens facing surface is formed of a light shielding member, and the outer peripheral surface is formed of a light transmissive member. According to this, while the cap is attached to the projection lens, the projection lens can be protected from scratches and the like, and even when light is projected from the projection lens, the light is blocked in the projection direction of the projection lens, Since the projection light leaks from the outer peripheral surface of the cap in the lateral direction of the projection lens, it is possible to determine whether or not the light is being projected even if the cap is attached to the projection lens. Further, even when there is an explainer on the projection side in a presentation or the like, this cap can be attached as a substitute for the image mute with almost no influence of the leaked light on the explainer. If the light transmissive member is semitransparent, the amount of light leaking from the outer peripheral surface of the cap can be set to the minimum amount necessary for determining the presence or absence of projected light.

A projection lens cap having a lens facing surface arranged to face the lens surface of the projection lens, and an outer peripheral surface surrounding the lens facing surface and fitted to the tip of the projection lens. The cap is formed of a light shielding member, and at least one hole is provided on the outer peripheral surface. According to this, while the cap is attached to the projection lens, the projection lens can be protected from scratches and the like, and even when light is projected from the projection lens, the light is blocked in the projection direction of the projection lens, Since the projection light leaks from the hole of the cap in the lateral direction of the projection lens, it is possible to determine whether the light is being projected even if the cap is attached to the projection lens. Further, even when there is an explainer on the projection side in a presentation or the like, this cap can be attached as a substitute for the image mute with almost no influence of the leaked light on the explainer. If the holes are provided in a mesh shape, in addition to the above effects, the mesh acts as a ventilation hole, which can contribute to cooling of the tip portion of the projection lens.

A projection lens cap having a lens facing surface arranged to face the lens surface of the projection lens, and an outer peripheral surface around the lens facing surface and fitted to the tip of the projection lens. The cap is formed of a light blocking member, and a light guide piece for guiding light is arranged so as to penetrate from the inside of the outer peripheral surface to the outside in the vicinity of the lens facing surface. According to this, while the cap is attached to the projection lens, the projection lens can be protected from scratches and the like, and even when light is projected from the projection lens, the light is blocked in the projection direction of the projection lens, Since the projection light leaks from the light guide piece in the side surface direction of the projection lens, it is possible to determine whether or not the light is being projected even if the cap is attached to the projection lens. Further, even when there is an explainer on the projection side in a presentation or the like, this cap can be attached as a substitute for the image mute with almost no influence of the leaked light on the explainer.

Further, there is proposed a projector in which the projection lens cap according to any one of the above claims is detachably attached to the projection lens. At this time, the projection lens includes a detection unit that detects that the cap is attached to the projection lens, and a voice output control unit that stops the output of voice in association with the detection of the projection lens attachment by the detection unit. By attaching the cap to the, it is possible to stop both the image display and the sound output even while the projector is operating.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a projection lens cap 1 according to an embodiment of the present invention.
0 is a perspective view of the projector 8 with its cap 10
The state where the projection lens 3 of 0 is mounted is shown. The cap 10 includes a lens facing surface 11 that is arranged to face the lens surface of the projection lens 3, and an outer peripheral surface 12 that is fitted around the lens facing surface 11 and is fitted to the tip portion of the projection lens 3. The lens facing surface 11 is formed of a light shielding member such as black plastic, while the outer peripheral surface 12 is formed of a light transmissive member capable of transmitting light. It should be noted that the light transmissive member forming the outer peripheral surface 12 is preferably one that transmits the minimum amount of light that can be perceived by human eyes, and therefore, it is preferably formed of translucent plastic or the like. Good. Further, an aluminum foil or the like may be attached to the inside of the lens facing surface 11 to form a mirror surface so that the cap 10 does not easily absorb heat. According to the projection lens cap 10, while the cap 10 is attached to the projection lens as shown in the figure, the projection lens can be protected from scratches and the like, and even if light is projected from the projection lens 3, projection is possible. Light is blocked by the lens facing surface 11 in the projection direction of the lens 3, and the outer peripheral surface 1 in the side surface direction of the projection lens 3.
Since the light leaks from 2, it is possible to determine whether the light is being projected even if the cap 10 is attached to the projection lens 3. Further, even when there is an explainer on the projection side in a presentation or the like, this cap can be attached as a substitute for the image mute with almost no influence of the leaked light on the explainer.

FIG. 2 is a perspective view showing another embodiment of the projection lens cap according to the present invention. In FIG.
(A) is a cap 10 provided with slits 12a on the outer peripheral surface 12 (the number of slits 12a may be appropriately determined, but 2 to 4 may be sufficient), and (b) is an outer periphery of the cap 10. The surface 12 is formed in the shape of a mesh 12b, and (c) is the outer peripheral surface 12 near the lens facing surface 11.
The rod-shaped light guide piece 13 is disposed through the above. In addition,
In the cases of (a) to (c), the entire surface of the cap 10 including the lens facing surface 11 is formed of a light shielding member such as black plastic. In the case of (a), the light leaks from the slit 12a, and in the case of (b), the light leaks from the mesh 12b, so that the presence or absence of the projection light by the projection lens 3 can be determined. In the case of (b), the heat generated from the projected light can be efficiently diffused through the mesh 12b. Further, in the case of (c) above, since the projection light is transmitted to the outside of the outer peripheral surface 12 of the cap 10 via the light guide piece 13, the presence or absence of the projection light by the projection lens 3 can be determined by the light. Note that the light guide piece 13 can be painted with any color, and in that case, that color is displayed during light projection.

Embodiment 2 Next, a project provided with the cap 10 will be described. (I) Main Configuration of Project FIG. 3 is a block diagram showing the main configuration of a three-panel projector for explaining the embodiment of the invention. As shown in the figure, the projector 100 includes a color light separation optical system 8 for separating the lamp 1 serving as an illumination light source and the illumination light of the lamp 1 into red (R), green (G), and blue (B) light. Liquid crystal panels 2R, 2G, 2 as light modulators that are irradiated with the respective colored lights and display an image in accordance with predetermined image information.
B, a cross dichroic prism 9 for combining the images generated by these liquid crystal panels, and a projection lens 3 for projecting the combined image. The projector 100 is
Further, a lamp drive circuit 1A for driving the lamp 1, an image processing circuit 2A for supplying image information to the liquid crystal panels 2R, 2G, 2B, a speaker 4 for outputting sound, an audio processing circuit 4A for supplying audio information to the speaker 4, A fan 5 for cooling the lamp 1 and / or the liquid crystal panels 2R, 2G, 2B, a fan drive circuit 5A for driving the fan 5,
A user interface 6 including an input device for inputting various control information and data to the projector 100,
Then, a central processing unit (CPU) 7 that controls the lamp driving circuit 1A, the image processing circuit 2A, the audio processing circuit 4A, the fan driving circuit 5A, and the user interface 6.
Equipped with. Furthermore, the cap 10 described in the first embodiment
However, it is held in the main body of the projector 100 by using a cable, a rope or the like.

Here, the lamp drive circuit 1A, the image processing circuit 2A, the audio processing circuit 4A, the fan drive circuit 5A, and the user interface 6 will be briefly described. The lamp drive circuit 1A is a power supply circuit for supplying drive power to the lamp, and transforms the power supplied from the outside to supply the power to the lamp 1. In this lamp drive circuit 1A, the amount of power supplied to the lamp 1 is controlled by the CPU 7, and the output brightness of the lamp 1 is adjusted accordingly. The image processing circuit 2A reads, for example, an image displayed on a personal computer or the like or an image signal stored therein beforehand and sends it to the corresponding liquid crystal panels 2R, 2G and 2B as RGB signals. Also, various settings for image display are performed here. The image processing circuit 2A is also controlled by the CPU 7. The voice processing circuit 4A processes a voice signal or the like taken in together with an image so as to be output from the speaker 4, and ON / OFF of voice output to the speaker 4 is controlled by the CPU 7. The fan drive circuit 5A is composed of a motor, etc., and includes the lamp 1 and / or the liquid crystal panels 2R, 2
Power is supplied to the fan 5 for sending cooling air to G and 2B, and the power supply amount is controlled by the CPU 7. It should be noted that recent high-intensity lamps generate a considerable amount of heat when used, so that cooling of the lamps has become particularly important. The user interface 6 is for inputting various control information and various data to the projector 100 from the outside, and the acquisition of an image signal from an external personal computer and the acquisition of a display image signal stored in the projector in advance are performed as follows. This is done. Also,
A push switch, which will be described later, is attached to the projection lens cap 10, and the ON / OFF signal of the switch is also fetched via the user interface 6.

In the above projector 100, the lamp 1 is turned on by the lamp driving circuit 1A. Then, the illumination light from the lamp 1 is separated into red (R), green (G), and blue (B) color lights by the color light separation optical system 8, and the separated color lights correspond to the RGB signals of the image, respectively. The liquid crystal panels 2R, 2G, and 2B provided are irradiated to display images, and then the respective images are cross dichroic prism 9.
And the combined image is projected from the projection lens 3 onto the screen 200 or the like. Also,
According to the audio information from the audio processing circuit 4A, audio is output from the speaker 4 in accordance with the image display. Further, while the main power is on, the fan drive circuit 5A
By this, the fan 5 is driven, and the temperature inside the projector is kept below a predetermined value. The drive of the fan 5 is usually automatically controlled by the CPU 7 or the like in accordance with the internal temperature condition.

(Ii) Configuration and Operation of Optical System of Projector FIG. 4 is a configuration diagram showing an optical system of the projector 100. The configuration and operation of the optical system will be described below with reference to FIG.

This optical system includes an illumination optical system 23, a color light separation optical system 8, a relay optical system 25, liquid crystal panels 2R, 2G,
2B, a cross dichroic prism 9 for combining color lights, a projection lens 3 and the like.

The illumination optical system 23 comprises a lamp 1, a reflector 20, and a first and a second which constitute an integrator lens.
It includes lens arrays 21 and 22, a reflection mirror 31 for adjusting the traveling direction of light, and a superposing lens 32. It should be noted that the reflection mirror 31 is not necessary in the case where the adjustment of the traveling direction of the illumination light is unnecessary.

The first lens array 21 has a structure in which small lenses 211 having a substantially rectangular contour are arranged in a matrix of M rows and N columns. Each small lens 211 forms a plurality of parallel light fluxes (that is, M ×
It is divided into (N) partial light beams, and each partial light beam is imaged in the vicinity of the second lens array 22. The contour shape of each small lens 211 is set to be substantially similar to the shape of the image forming area of the liquid crystal panels 2R, 2G, 2B. For example, if the aspect ratio (ratio of horizontal and vertical dimensions) of the image forming area of the liquid crystal panel is 4: 3, the aspect ratio of each small lens is also set to 4: 3. The second lens array 22 also has a configuration in which the small lenses 221 are arranged in a matrix of M rows and N columns corresponding to the small lenses 211 of the first lens array 21.

The color light separation optical system 8 includes two dichroic mirrors 41 and 42 and a reflection mirror 43, and outputs the light emitted from the superposing lens 32 of the illumination optical system 23 to red,
It has the function of separating light into three colors, green and blue. The relay optical system 25 is an optical path corresponding to the transmitted light from the dichroic mirror 42, and includes the incident side lens 54 and the reflection mirror 7.
1, 72 and a relay lens 73.

The liquid crystal panels 2R, 2G and 2B are, for example,
It uses a polysilicon TFT as a switching element, and is adhesively fixed to the cross dichroic prism 9 via a fixing member so as to face the three side surfaces of the cross dichroic prism 9. In addition, each liquid crystal panel 2
An incident side polarizing plate 60 is provided on the light incident / exiting surface side of R, 2G, and 2B.
R, 60G, and 60B are disposed, and emission side polarization plates 61R, 61G, and 61B are disposed on the light emission surface side.

The cross dichroic prism 9 is red,
A color image is formed by combining color lights of three colors, green and blue. A dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are formed at the interfaces of four right angle prisms. Are formed in a substantially X shape, and the three color lights are combined by these dielectric multilayer films. The projection lens 3 is arranged on the exit surface side of the cross dichroic prism 9.

Next, the operation of the above optical system will be described. The light emitted from the lamp 1 is reflected by the reflector 20 and enters the integrator lens composed of the first and second lens arrays 21 and 22. The integrator lens forms an image formed by each lens cell of the first lens array 21 on the image display surface of each liquid crystal panel 2R, 2G, 2B by the second lens array 22 and the superimposing lens 32, and The effect of improving the utilization rate of the light and improving the uneven lighting. The light emitted from the superimposing lens 32 subsequently enters the color light separation optical system 8.

The first dichroic mirror 41 of the color light separation optical system 8 reflects the red light component of the luminous flux emitted from the illumination optical system 23 and transmits the blue light component and the green light component. The red light reflected by the first dichroic mirror 41 enters the field lens 51 via the reflection mirror 43, and further, the liquid crystal panel 2 for red light.
Reach R The field lens 51 converts each partial luminous flux into a luminous flux parallel to the central axis (chief ray) thereof. The field lenses 52 and 53 provided in front of the other liquid crystal panels 2G and 2B also operate similarly.

Of the blue light and the green light transmitted through the first dichroic mirror 41, the green light is reflected by the second dichroic mirror 42, passes through the field lens 52, and reaches the liquid crystal panel 2G for green light. On the other hand, the blue light passes through the second dichroic mirror 42, passes through the relay optical system 25, and further passes through the field lens 53 to reach the liquid crystal panel 2B for blue light.

The red, green, and blue color lights separated by the color light separation optical system 8 are incident on the liquid crystal panels 2R, 2G, and 2B, and are reflected by the incident side polarization plates 60R, 60G, and 60B, and only specific polarized light is generated. To be done. After that, each polarized light is modulated in each liquid crystal panel 2R, 2G, 2B according to the image information given from the image processing circuit 2A, and is emitted to the emission side light plates 61R, 61G, 61B as modulated light. In the exit side polarization plates 61R, 61G and 61B, only specific polarized light of the modulated light is transmitted and is incident on the cross dichroic prism 9. Then, the respective color lights are combined by the cross dichroic prism 9 to become combined light, which is projected from the projection lens 3 onto the screen 200 as a color image.

Incidentally, at a predetermined position of the illumination optical system 23, for example, between the second lens array 22 and the superposing lens 32,
When a polarization beam splitter that aligns the illumination light including both P-polarized light and S-polarized light from the lamp 1 with one polarized light is disposed, the light incident from the lamp 1 is wasted in the liquid crystal panels 2R, 2G, and 2B. It is possible to use almost all of them.

(Iii) Configuration Related to Projection Lens Cap and Operation of the Cap FIG. 5 is a perspective view showing the projector according to the embodiment of the present invention with the cap removed from the projection lens. The projection lens 3 is arranged on the front surface of the projector 100, and the cap 10 is attached to and detached from the projection lens 3.
Is held by the projector 100 via the attachment cord 15. Further, a push switch 14 is attached to the inside of the outer peripheral surface 12 of the cap 10, and the ON / OFF signal of the push switch 14 is transmitted from the attachment cord 1.
It is sent to the user interface 6 shown in FIG.

In the projector 100, the cap 10 prevents damage to the projection lens 3 while the cap 10 is mounted on the projection lens 3. Further, even if light is projected from the projection lens 3 while the cap 10 is attached to the projection lens 3, the light is blocked by the lens facing surface 11 in the projection direction of the projection lens 3, and in the side surface direction of the projection lens 3. Light leaks from the outer peripheral surface 12. Therefore, even if the cap 10 is attached to the projection lens 3, it is possible to determine whether or not light is being projected. Further, even when there is an explainer on the projection side in a presentation or the like, the cap 10 can be attached as a substitute for the image mute with almost no influence of leaked light on the explainer.

Further, the following functions are added to the projector 100. That is, the projector 10
When the cap 10 is attached to the projection lens 3 while the main power source of 0 is turned on, the push switch 14 inside the cap 10 is pressed by the fitting with the projection lens 3 to be turned on. The signal indicating the ON state is sent to the user interface 6 via the signal line built in the attachment rope 15. When the ON signal of the push switch 14 is taken into the user interface 6, CP
U7 determines that the cap 10 is attached to the projection lens 3, and sends a signal for stopping the audio output from the speaker 4 to the audio processing circuit 4A, and the audio processing circuit 4A stops the audio output of the speaker 4. . And cap 1
When 0 is removed from the projection lens 3, the stop of the sound output is released, and the normal sound output control is resumed. Therefore, even if audio is being output from the speaker 4, the audio output is stopped when the cap 10 is attached to the projection lens 3, and the cap 10 is attached to the projection lens 3 in the stopped state. Maintained while As a result, when a cap 10 is attached to the projection lens 3 in the light projection state to temporarily stop the image display on the screen at the time of a presentation or the like, the output of the sound is also stopped at the same time. Can make the stop more effective.

Here, when the cap 10 is attached to the projection lens 3 and the main power source of the projector is ON, the audio output is stopped, but in addition to this, Separately from this, when the cap 10 is mounted on the projection lens 3, the lamp drive circuit 1A and the fan drive circuit 5A are controlled to appropriately combine the output brightness reduction of the lamp 1 and the speed reduction of the fan 5 and the like. You may let me.

By the way, in the above-described embodiment, the three-plate type projector in which three liquid crystal panels are provided corresponding to each of the RGB signals has been described as an example, but the projector of the present invention employs another number of liquid crystal panels. It is also possible to adopt a so-called single-panel type projector using one liquid crystal panel. Further, although the liquid crystal panel is a transmissive type that transmits and modulates light, it may be a reflective type that modulates and emits incident light while reflecting it.

[0033]

According to the projection lens cap of the present invention or the projector provided therewith, in addition to protecting the projection lens, the projection light from the projection lens is basically blocked.
It becomes possible to determine the presence or absence of projection light by causing leakage light in a direction that is less influential to the operator or explainer on the projection side, thus contributing to the safe use of the projector.
It is also possible to use this cap as an alternative to image mute at the time of presentation.

[Brief description of drawings]

FIG. 1 is a diagram showing a projection lens cap according to an embodiment of the present invention, and is a perspective view showing a state in which the cap is mounted on a projection lens of a projector.

2A and 2B are perspective views showing another embodiment of the projection lens cap according to the present invention, wherein FIG. 2A is a cap outer peripheral surface provided with slits, and FIG. 2B is a mesh of the cap outer peripheral surface. In FIG. 3C, the light guide piece is formed so as to penetrate the outer peripheral surface near the lens facing surface.

FIG. 3 is a block diagram showing a main configuration of a projector according to an embodiment of the invention.

4 is a configuration diagram showing an optical system of the projector of FIG.

FIG. 5 is a perspective view showing the projector according to the embodiment of the invention with the cap removed from the projection lens.

[Explanation of symbols]

1 lamp 1A lamp drive circuit 2A image processing circuit 2B, 2G, 2R liquid crystal panel 3 Projection lens 4 speakers 4A audio processing circuit 5 fans 5A fan drive circuit 6 User interface 7 Central processing unit (CPU) 8-color light separation optical system 9 Cross dichroic prism 10 Projection lens cap 11 Lens-facing surface of projection lens cap 12 Outer surface of projection lens cap 12a hole 12b mesh 13 Light guide piece 14 push switch 15 Cable line built-in cap 100 projector

Claims (7)

[Claims] 1. A projection lens cap comprising: a lens facing surface, which is arranged to face the lens surface of the projection lens; and an outer peripheral surface around the lens facing surface, which is fitted to the tip of the projection lens. A cap for a projection lens, wherein the lens facing surface is formed of a light shielding member, and the outer peripheral surface is formed of a light transmissive member. 2. The projection lens cap according to claim 1, wherein the light transmissive member is semitransparent. 3. A projection lens cap comprising: a lens facing surface arranged to face the lens surface of the projection lens; and an outer peripheral surface surrounding the lens facing surface and fitted to a tip portion of the projection lens. A cap for a projection lens, wherein the cap is formed of a light shielding member, and at least one hole is provided in the outer peripheral surface. 4. The projection lens cap according to claim 3, wherein the holes are provided in a mesh shape. 5. A projection lens cap comprising: a lens facing surface, which is arranged to face the lens surface of the projection lens; and an outer peripheral surface around the lens facing surface, which is fitted to the tip of the projection lens. A projection lens cap, characterized in that the cap is formed of a light shielding member, and a light guide piece for guiding light is arranged so as to penetrate from the inside of the outer peripheral surface to the outside in the vicinity of the lens facing surface. 6. A projector for performing projection using a projection lens, wherein the projection lens cap according to claim 1 is detachably attached to the projection lens. 7. A detection means for detecting that the cap is attached to a projection lens, and an audio output control means for stopping the output of audio in synchronization with the detection of the attachment of the projection lens by the detection means. The projector according to claim 6, characterized in that: