JPH0259691A - Projection relation detecting device - Google Patents

Abstract

PURPOSE:To simply measure an interval between a projection type television device and a screen by providing a transmitting/receiving element on the same plane as the projection surface on which a projection tube is provided and measuring a transfer time of an ultrasonic wave, etc., extending from transmission to reception. CONSTITUTION:First of all, transmitting/receiving elements 3a, 3b for transmitting or receiving an ultrasonic wave or a light beam which becomes a test signal for measuring a distance between a body 1 and a screen are provided so as to be separated from each other on the projection surface of the body 1. In a system using an ultrasonic wave, a transmitting signal from one element 3a of a pair of transmitting/receiving elements is received by the other element 3b, or reception and transmission are executed by the respective transmitting/ receiving elements 3a, 3b, and by measuring a time difference between the transmission timing and the reception timing, a measurement of the distance is executed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a projection relationship detection device that measures the projection distance of a projection television apparatus to a screen and detects the parallelism of the screen.

Conventional technology There are two types of projection television equipment: floor-standing type and ceiling-suspended type, and the distance between the projection television equipment and the screen depends on the effective screen size of the screen. It is decided. Moreover, if the projection surface of the projection television device and the screen screen are not parallel,
Distortion occurs on the projected screen. Therefore, when a projection television device is delivered to a user, the construction personnel usually check the distance between the projection television device and the screen.
, Title of the invention Projection-related detection device 2, Claims (1) A transmitting means for transmitting and receiving ultrasonic signals disposed on the same plane as the projection surface of a projection television device 3. Stage and receiving means. , a first signal indicating the transmission timing of the transmitting means and a second signal indicating the receiving timing of the ultrasonic signal transmitted from the transmitting means, reflected by the screen and received by the receiving means, and the 1. A projection relationship detection device comprising distance measuring means for detecting a delay time between a first signal and a second signal and calculating the distance between the projection television screen/device and the screen from this delay time.

(2) A light-emitting means disposed on the same plane as the projection surface of the projection television apparatus, and a light-emitting means disposed on the same plane as the projection surface from which the light emitted from the light-emitting means is reflected by the screen and receives all of the fluorescent light. After measuring the light receiving means and the detection distance and parallelism for detecting the incident angle of light to the light receiving means, the light receiving means is completely fixed to the floor or ceiling with screws or the like.

Problems to be Solved by the Invention However, there are major problems in completely fixing the television device as described above. That is, since the screen is generally installed on the wall side of the room, the projection television device is installed on the center side of the room with respect to the screen. As a precaution, the projection television device, which is a relatively large device, is fixed approximately at the center of the floor of the room, although it may not be fixed on the ceiling. If the projection television set is fixed in the center of the room in this way, the aesthetic appearance of the room will be spoiled and the way the room can be used will be restricted. Therefore, it is possible to move the projection television device on a wagon or the like, but as mentioned above, the distance and parallelism between the projection television device and the screen directly affect the quality of the reproduced image. . It is also very inconvenient to measure the distance and check the parallelism every time you use a projection television device.

The present invention solves all of the above problems, and aims to provide a projection relationship detection device that can easily measure the distance between a projection TV set and a screen without using a measuring device such as a tape measure, and ensure parallelism. That is.

Means for Solving the Problems In order to achieve the above object, the projection relationship detection device of the present invention includes a transmitting and receiving element provided on the same plane as the projection surface on which the projection tube of the projection television device is disposed, By measuring the time from transmission to reception by the transmitter/receiver element, the distance between the projection television set and the screen is measured based on the known propagation velocity of ultrasonic waves. In addition, by using light, a pair of light receiving and light emitting elements are installed on the same plane as the projection surface, and by detecting all angles of incidence of reflected light to the light receiving element, the distance between the light emitting element and the light receiving element can be adjusted. In particular, it measures the distance between the projection television device and the screen.

Effect According to the above configuration, the distance CL=l/- can be calculated from the time from transmission to reception of the transmitter/receiver element and the propagation velocity (V) of the ultrasonic wave, and from the distance and the distance between the receiver 1 light emitting elements (effect). This distance can be easily measured, and by measuring this distance at at least two locations on the screen, the parallelism of the screen to the projection surface can be detected.Then, the projection relationship between the projection surface and the screen of these projection television devices can be detected. This measurement can be achieved electrically and automatically, for example, by pressing a button on the user's part, without the user's own measurement using a tape measure or the like. It is easy to use and can be installed with appropriate distance spacing and parallelism without any troublesome effort.

Embodiment Hereinafter, a projection relationship detection device for detecting the projection relationship between a projection type television display device and a screen according to an embodiment of the present invention will be described with reference to the drawings.

FIGS. 1(IL), 1(b), and 1(0) are a perspective view, a side view, and a plan view showing the configuration of a projection television apparatus in which the projection relationship detection device of this embodiment is integrally provided. In Fig. 1, 1 is a projection television device main body (hereinafter abbreviated as the main body) 1, and the distance between the main body 1 and the screen 2 is Transmitting/receiving elements 3a and 3b are provided for transmitting or receiving ultrasonic waves or light serving as test signals for all measurements. The distance between the main body 1 and the screen 2 is uniquely determined by the size of the projection screen, in other words, the size of the screen 2, and in this embodiment, the distance between the projection surface of the main body 1 and the screen 2 is determined. The parallelism between the projection surface and the screen is detected by measuring the distance at at least two locations and comparing these values. Therefore, a pair of transmitting/receiving (optical) elements 3a, ・ab are spaced apart from each other on the projection surface of the main body 1.
1, and a pair of transmitting/receiving elements 31 in the method using ultrasonic waves.
The transmission signal from one element 3a of L is received by the external element 3b, or the transmission signal from each of the transmitting and receiving elements 3m, 3
b performs reception and transmission and measures distance. On the other hand, in the case of the optical method, the light signals from the light emitting elements 3&, (3b) are received by the light receiving elements 3b, (32L), and the distance is measured based on the received light again.

FIG. 2 is a schematic plan view for explaining the principle of distance measurement by the optical projection-related detection device.

In FIG. 2, 3c is a lens for projecting and condensing light from the light receiving/emitting elements aa and 3b. The optical signal for distance measurement from the light emitting element 3b passes through the lens 3C, is reflected by the screen 2, and then passes through the other lens 3G.
to the light receiving element 3a.

The light receiving element 31L has a plurality of unit elements arranged in a nine array shape from the optical axis of the lens 30 in the direction a in FIG. 2. Second
In the figure, when the light-emitting element 3b' is arranged at the position of the light-receiving element 3a, the light-receiving element 3a/ arranged at the position of the light-emitting element 3b is arranged in a straight line in the direction shown in Fig. 2. It consists of arranged play elements. Therefore, the larger the reflection angle θ on the screen 2, the more the lens 3 of the light receiving element 3 &
The optical signal is incident on the outside of the optical axis of c (in the direction of a).

If the distance from the center of the lens 3G to the light-receiving surface of the light-receiving element 3a is f, and the distance from the optical axis of the lens 3C to the incident position of the light-receiving element 3 is x, then the amount of light incident on the optical axis of the lens 3C is The slope θ satisfies -〇=-. The inclination θ of the incident light matches the reflection angle on the screen 2, and the reflection angle θ is the distance between the main body 1 and the screen 2, the distance between the main body 1 and the screen 2, and the distance between the light emitting element 3b and one lens 3c.
If the distance from the center of lens 3c to the center (optical axis) of the other lens 3c is l, then 10=! satisfy. As a result, the distance can be determined by L=lf/x. By performing the above measurements at multiple points and finding the distance difference, the main body 1
It becomes possible to detect the parallelism between the projection surface and the screen screen. Note that the above-mentioned arithmetic processing can be easily realized with an arithmetic device such as a CPU, and its explanation will be omitted here.

Next, the ultrasonic projection-related detection device will be described below with reference to FIG. FIG. 3 is a block diagram showing the configuration of the ultrasonic projection-related detection device of this embodiment. In FIG. 3, 11 is a timing pulse generator that generates timing pulses, and 12 is a pulse modulator that modulates the timing pulses from the HALUS generator 11 with signals 70 and 17 so as to be suitable for driving the transmitting/receiving elements 13 and 14. It is. The distance between main body 1 and screen 2 is 1.5 for general consumer use.
If the distance is about 35 m, and the ultrasonic wave is about 40 m to 70 m, the distance between the two can be detected with relatively high accuracy. The timing pulse modulated by the pulse modulator 12 is amplified by the amplifier 16 and transmitted from the transmitting element 13. The 70 to 17 ultrasonic signals from the transmitting element 13 reflected by the screen 2 are received by the receiving element 14. 16 is an amplifier for amplifying the ultrasonic signal received by the receiving element 14; 17 is a detector for outputting a timing pulse from the ultrasonic signal amplified by the amplifier 16; and 18 is a waveform shaping circuit. Reference numeral 19 denotes a distance setting circuit which inputs the output timing pulse of the timing pulse generator 11 and applies a delay time corresponding to the projection size to all timing pulses. The distance between the projection surface and the screen that is optimal for the projection size is uniquely determined by a proportional relationship as described above. As is well known, the transmission speed of ultrasonic waves in the air is
Speed V: 331+0.6t (VB); t is temperature. The transmission time T required for the ultrasonic signal transmitted from the transmitting element 13 to be received by the receiving element 14 is T=2L/ma(S). In accordance with the screen size setting in the input means (not shown), the distance and transmission time Ti are determined by the calculating means (not shown), and based on the output of this calculating means, the timing pulse is calculated by the distance setting circuit 19. Delay by T. 2o is a distance judgment circuit,
Timing pulse P1 obtained from waveform shaping circuit 18 and timing pulse P2 delayed by distance setting circuit 19
It is determined whether or not the received timing pulse P coincides with the timing pulse P2 in time. The determination result of this distance determination circuit 20 is then displayed on the display section 21. The display method of the display unit 21 is such that, for example, if the distance between the main body 1 and the screen 2 matches the projection size, a light emitting diode is made to emit light.

In the above configuration, the pulse generator 11 and the pulse modulator 12
, the amplifier 15 and the transmitting element 13 constitute a transmitting means, the receiving element 14, the amplifier 16, the detector 17, and the waveform shaping circuit 18 constitute a receiving means, and the distance setting circuit 19 and the distance determining circuit 2o constitute a distance measuring means. are doing.

As described above, according to this embodiment, the main body 1 and the screen 2
It can be easily detected whether the distance from By performing this distance detection at a plurality of locations, it is possible to detect the parallelism of the screen to the projection surface. As a result, the projection television device and the screen 2 can all be arranged in parallel with each other in a position suitable for the projection size, and a good projected image without projection distortion can be obtained.

In addition, in this embodiment, the calculation means and the distance setting circuit 19
, distance determination circuit 20, etc., can be realized by, for example, a 4-bit microprocessor. However, in this embodiment, the display unit 21 displays whether or not the interval between the main body 1 and the free leaf 20 is compatible with the set screen size. Displaying the amount of distance deviated can also be easily replaced based on well-known technology.

Effects of the Invention According to the present invention, the transmitting (light) means and the receiving (light) means are arranged on the projection surface on which the projection tube of the projection television device is arranged, and in the ultrasonic method, the screen of the television device is By detecting the propagation delay time of the ultrasonic waves corresponding to the distance between the two, in the optical method, the distance between the two can be easily measured by detecting the angle of incidence of the screen reflected light on the light receiving element. And no, it fits the screen size
A television device and a screen can be easily arranged in the interval. Furthermore, by measuring distances at multiple locations on the screen, comparing the results, and arranging the locations so that there are no differences in the measured distances, it is possible to obtain accurate parallelism, resulting in a good projected image without projection distortion. can be obtained.

[Brief explanation of the drawing]

Figures 1 (IL), (b), and (C) are perspective views, side views, and plan views showing the configuration of a projection relationship detection device according to an embodiment of the present invention, and Figure 2 is a diagram of an optical projection relationship detection device. A plan view showing the measurement principle, and Figure 3 is an ultrasonic projection-related inspection. Pro 1 showing the configuration of the button device. This is a diagram. 1...Body, 2...Screen, 3.
...Transmission/reception element. Name of agent Patent attorney Shigetaka Awano and 1 other person (Denori 3 mountains. 3b-Issho Rahii Genri-ko 1st ■ Figure Damn?) (b) Kukuzu V3α Figure 3 1/l? /degree

Claims (2)

[Claims] (1) A transmitting means and a receiving means disposed on the same plane as the projection surface of the projection television apparatus for transmitting and receiving ultrasonic signals, a first signal indicating the transmission timing of the transmitting means, and the transmitting means A second signal indicating the reception timing of the ultrasonic signal transmitted from the ultrasonic wave, reflected by the screen, and received by the receiving means is input, a delay time between the first signal and the second signal is detected, and this delay is detected. 1. A projection relationship detection device comprising distance measuring means for calculating the distance between a projection television device and a screen based on time. (2) a light emitting means disposed on the same plane as the projection surface of the projection television apparatus; and a light emitting means disposed on the same plane as the projection surface for receiving light emitted from the light emitting means and reflected on the screen. A projection television apparatus is detected from a light receiving means, a detecting means for detecting the angle of incidence of light on the light receiving means, a detection output indicating the angle of incidence of the detecting means, and information indicating the distance between the light emitting means and the light receiving means. A projection relationship detection device comprising: calculation means for calculating a distance from a screen.