JP2005258214A - Projecting method in planetarium insitution - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To resolve the difference in black level when simultaneously using a plurality of kinds of projectors in planetarium facilities. <P>SOLUTION: In case that black levels of projected images are not identical when simultaneously using two or more kinds of projectors in planetarium facilities wherein several kinds of projectors exist together, the light quantity is optically adjusted by a fader 6 provided in a projector P having a black level in a brighter side to equalize the black levels. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

    The present invention relates to a video image projection device on a dome screen, and more particularly to a video image projection device using a video image projector optimal for a planetarium or the like.

For facilities that project images with a single projector such as a projector, facilities that project images by collaborating with different types of projectors, mainly spherical screen image facilities that provide simulated images Exists. A typical example is the planetarium facility. As is well known, the planetarium facility has the essence of reproducing the starry sky by projecting a star image on a dome screen from a star projector. On the other hand, a planetarium projection device (hereinafter abbreviated as “planetarium”) has a planetary projection device that projects planets separately from stars, and a skyline projection device that projects landscapes such as the ground as the production technique evolves. It comes equipped with a projection device for various images such as constellation pictures, coordinate lines, nebulae, star clusters, pointers, and more recently it projects natural phenomena that occur in the sky, such as lightning and aurora, and artificial objects such as spaceships. It has also been equipped with a projector for. The equipment used there is not limited to conventional optical equipment using films and original plates, and electronic equipment such as video image projectors are also used. Not only the video recorded on the disc but also the video generated by the computer in real time as needed is adopted.
JP 2000-66582 A

  As mentioned above, when multiple types of projectors are mixed in a planetarium facility, there is no problem if they are optical ones, but when video image projectors are mixed, the black level of the projected image is different. Occurs.

  For example, when projecting an image on a dome screen using a liquid crystal or DLP video image projector while projecting the starry sky on a dome screen with a stellar projector that is an optical projector, the contrast ratio of the latter projector Because of the low brightness, the black level was projected brightly, making it impossible to produce low-light effects such as faint stars and the Milky Way. Therefore, in order to avoid this, an expensive and dark video image projector such as a CRT projector must be used.

  However, the CRT projector has a problem that it cannot express vivid colors because the amount of light is small in order to project onto a large dome of a planetarium. When it was unavoidable to use a liquid crystal projector, it was used with a movable shutter that covered the entire surface of the lens when it was not projected. In this case, it was impossible to project an image at the same time as the star, and even if it was forcibly projected, the problem was that the image of the star was significantly deteriorated.

  The present invention was created to solve the above problems, and an object thereof is to provide a projection method in which the black levels of the projected images on the dome screen match even when a plurality of types of projectors are used simultaneously. And

  The projection method of the present invention is suitable for a projector having a brighter black level when the black level of the projected image does not match when two or more types of projection devices are used simultaneously in a planetarium facility where a plurality of types of projectors are mixed. The black level is matched by optically adjusting the amount of light by the provided fade device.

  The present invention also relates to a fading device, and also discloses an invention as a means for optically adjusting the amount of light by arranging a movable filter or aperture on the optical path of the projector in the above invention.

Further, the following inventions are also disclosed regarding the control method of the fade device.
(1) Program the amount of light adjustment in advance according to the projected image to be projected by projection so that the amount of light changes continuously according to the projection scene.
(2) The brightness level of the entire projection screen and the brightness distribution of the entire projection screen are detected from the video signals sent to each projector used simultaneously, and are automatically reflected in accordance with the video signal by reflecting them in the light amount adjustment amount. Adjust the black level.
(3) When projecting a large screen on a planetarium dome with multiple projectors, video signals sent to each projector are batched so that the black level of each projector does not vary. To improve the contrast ratio while matching the black level of the entire large screen.

  In the projection method of the present invention, when the projector is used simultaneously with an optical projector such as a star projector, the black level is projected in accordance with the amount of light reduced by a fade device. In addition, when only the video image projector is used, the image is projected without limiting the amount of light, thereby projecting the original bright and colorful image of the video image projector.

  By the way, as a characteristic of the dome screen, when a bright image is projected on a part, there is a phenomenon of mutual reflection in which reflected light from the projected part is repeatedly reflected on the entire screen and the background level (degree of black) of the screen increases. Therefore, using this characteristic, when the mutual reflection by the screen of the projected image exceeds the black level of the video image projector, it is projected with the total amount of light, and when it is less than this, the amount of light is adjusted to maintain the apparent black level To do.

  According to the projection method of the present invention having the above configuration, even when the starry sky is projected by an optical projector in a planetarium, liquid crystal or DLP video can be used as an auxiliary projector without worrying about the black level problem. Since an image projector can be used, it is not necessary to use a CRT-type video image projector, and it is possible to perform inexpensive and vivid color expression.

  In addition, as a means for adjusting the light quantity of the video image projector, a means for optically adjusting the light quantity by arranging a movable filter or aperture on the optical path of the projector is adopted. Since the projector can be used for implementing the present invention simply by adding the adjusting means to the projector, the present invention can be implemented at a very low cost.

  Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a block diagram showing an electric circuit of a video image projector and its control device for carrying out the projection method of the present invention. Reference numeral P in the figure denotes a video image projector, and an optical fade device 6 for adjusting the amount of projection light is arranged on the optical path. The fade device 6 is driven by a fade controller 5, and a control signal is sent to the fade controller from the main controller 1 having a function of determining a fade amount for adjusting the amount of light.

  The main controller 1 has a fade rate calculation unit 2 for determining the fade amount. The brightness level of the video image projector P is input to the fade rate calculation unit, and the time code and ON / OFF of the external device are set. The dome illuminance from the signal or sensor is input, and the optimum fade amount is calculated based on these values. Reference numeral 3 in the figure denotes a luminance signal adder for outputting the luminance level of the video signal to the video image projector P distributed by the signal distributor 4 to the fade rate calculation unit 2.

  Next, the flow of a specific procedure of control in the control device will be described with reference to the flowcharts of FIGS. FIG. 6 is a diagram showing an outline of the procedure. Here, the video output of the video image projector is integrated (procedure S1), then the background level is calculated (procedure S2), and the above background level is compared with the base illuminance of the video image projector (procedure S3). When there is a difference in numerical values, the fade rate is changed (steps S4 and S5).

  FIG. 7 is a diagram showing details of the procedures S1 and S2. Here, the luminance level of the input signal to the video image projector is integrated per unit time (1 line, 1 frame, etc.), the video output of all projectors is integrated, the output of the video image projector and the planetarium or slide projection Check the lighting status of other projectors such as projectors (procedure S11), add their video outputs (procedure S12), and calculate the background level from the ratio of mutual reflection of the dome (reflectance, diameter, etc.) (Procedure S13).

  FIG. 8 is a diagram showing details of the procedure S4. Here, the result of the step 13 is compared with the base illuminance of the video image projector, and when there is a difference in numerical value, the difference is passed to the fade rate changing process (step S14).

  FIG. 9 is a diagram showing details of the procedure S5. Here, only when the base illuminance of the video image projector exceeds the background of the dome, the fade rate corresponding to the difference is read from the fade reference table (steps S15 and S16), and the fade rate is output. If the base illuminance of the video image projector does not exceed the background of the dome, the fade is fully opened (step S17).

  Next, a specific example of the fade device will be described. FIG. 2 is a diagram showing a first embodiment of the fade device. In this fading device 16, a filter having a different density is arranged in each window of the disc 17 located in the optical path of the video image projector in a revolver type by rotation, and the disc is driven by a pulse output from a fade controller. It is a means for optically adjusting the amount of light by rotating by a controlled motor 19.

  FIG. 3 is a diagram showing a second embodiment of the fade device. In this fade device 26, a motor 28 that is driven and controlled by a pulse output from a fade controller is used as means for optically adjusting the amount of light by opening and closing the iris diaphragm 27 located in the optical path of the video image projector.

  FIG. 4 is a diagram showing a third embodiment of the fade device. In this fading device 36, the motor is driven and controlled by the pulse output from the fade controller, and the optical position is changed by changing the mutual position of the filter composed of a pair of deflecting plates 37 and 38 located in the optical path of the video image projector. As a means to adjust the amount of light.

  FIG. 5 is a diagram showing a fourth embodiment of the fade device. This fade device 46 is incorporated in the light source section of a liquid crystal projector type video image projector, and is optically moved by moving a movable slit 51 located in the optical path by a motor that is driven and controlled by a pulse output from a fade controller. As a means to adjust the amount of light. In the figure, reference numeral 47 is a parabolic mirror of the light source unit, 48 is a lamp, 49 is a lens array, and 50 is a PS polarization conversion element.

Block diagram of an apparatus for carrying out the projection method of the present invention Same as above, perspective view of the first embodiment of the fade device portion Same as above, side view of second embodiment of fading device portion Same as above, side view of third embodiment of fading device portion Same as above, sectional view of the fourth embodiment of the fade device Same as above, flowchart showing processing flow Same as above, flowchart showing processing flow Same as above, flowchart showing processing flow Same as above, flowchart showing processing flow

Explanation of symbols

P Projector 6 Fade device 16 Fade device of the first embodiment 26 Fade device of the second embodiment 36 Fade device of the third embodiment 46 Fade device of the fourth embodiment

Claims (6)

  In a planetarium facility where multiple types of projectors coexist, when two or more types of projection devices are used at the same time, if the black level of the projected image does not match, the light is projected by the fade device provided on the projector with the brighter black level A method for projecting in a planetarium facility, characterized by adjusting the amount of light to match the black level.   2. The projection method in a planetarium facility according to claim 1, wherein the projector provided with the fade device is a video image projector.   3. The projection method in a planetarium facility according to claim 2, wherein the light quantity is optically adjusted by arranging a movable filter or aperture on the optical path of the projector.   4. A projection method in a planetarium facility according to claim 2 or 3, wherein a light amount adjustment amount is programmed in advance according to a projected image scheduled to be projected by a projector, and the light amount is continuously changed according to a projection scene.   By detecting the brightness level of the entire projection screen and the brightness distribution of the entire projection screen from the video signal sent to each projector that is used simultaneously, the black level is automatically adjusted according to the video signal by reflecting it in the amount of light adjustment. 4. The method for projecting in a planetarium facility according to claim 2 or 3, wherein the adjustment is performed. When projecting a large screen on a planetarium dome with multiple projectors, the video signals sent to each projector are processed in a batch so that the black level of each projector does not vary. 4. A projection method in a planetarium facility according to claim 2, wherein the contrast ratio is improved while matching the black level of the entire large screen.

Images