JP2788959B2 - Laser graphic display device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser graphic display device that scans a laser beam two-dimensionally and reproduces a line image on a screen, and more particularly, to a laser beam display device. The present invention relates to a technique for compressing point coordinate group data to be specified.

[Conventional technology]

FIG. 2 shows a laser beam scanning unit of a conventional laser graphic display device.

The laser graphic display utilizes the high linearity of the laser beam and the afterimage effect of human vision. As shown in FIG. 2, a laser beam emitted from a laser light source 1 is reflected by a pair of reflecting mirrors 2 and 3 that can reflect in two directions, horizontal and vertical, and the rotation angle of each of the reflecting mirrors is set to a corresponding galvano scanner 4. The laser beam is two-dimensionally scanned on the screen 6 by adjusting the speed at 5 and 5 to display characters and line patterns.

Therefore, basically, the laser beam scans along a predetermined route and route and displays image information which is linearized, that is, a so-called one-stroke pattern. However, complicated and multicolor image reproduction is possible by optically shuttering the laser beam at an appropriate timing to jump the laser beam spot or by using a multicolor laser beam.

By the way, in order to be visually recognized as an afterimage by the human eye, data specifying a predetermined path, that is, a line pattern, must be repeatedly output to the laser beam scanning unit at a speed of 10 to several tens of times per second. Such data is composed of a group of point coordinates that exist discontinuously along the line pattern, and is hereinafter referred to as dot data. The dot data is sent to a pair of galvano scanners at a high speed in a time series according to the route of the pattern.

[Problems to be solved by the invention]

The above-described discontinuous dot data is obtained by deleting and compressing primary data (hereinafter referred to as single-stroke data) including continuous point group coordinate data and route data defining a predetermined route pattern at an appropriate density and interval. Created. Conventionally, compression processing of such one-stroke data has been conventionally performed manually using a tablet. However, in order to reproduce a predetermined line pattern clearly and faithfully, this data compression operation requires delicate consideration and skill, and there is a problem that the operation time becomes long.

[Means to solve the problem]

An object of the present invention is to provide a laser graphic display device capable of automatically compressing one-stroke data and efficiently outputting high-quality dot data in order to solve the above-mentioned problems of the conventional technology. With the goal.

In order to achieve this object, according to the present invention, a laser graphic display device identifies a corner portion and a curved portion from a line pattern defined by one-stroke data, and a straight portion, respectively, and compares the corner portion and the curved portion from the corner portion and the curved portion. The processing unit has a processing unit for automatically compressing data and creating discontinuous dot data by deleting point coordinates as much as possible and deleting relatively many point coordinates from a straight line portion.

(Operation)

According to the present invention, the dot data created by the processing unit is output to the laser beam scanning unit in a time series according to the route information of the repetitive line pattern at high speed and visually reproduced. In this case, since the dot data is arranged at a relatively high density at the corners and the curved portions of the line pattern, these portions are visually emphasized and a high quality image is reproduced, and at the same time a relatively low density is obtained at the straight line portion. Because they are arranged,
Data compression is efficiently performed on the entire dot data.

〔Example〕

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of a laser graphic display device according to the present invention. The image scanner or TV camera 7 photoelectrically converts the two-dimensional image information to be reproduced and outputs bitmap information.
The CPU 8 composed of a personal computer or the like processes the video signal input from the TV camera 7, that is, bitmap information, creates dot data, and outputs the dot data to the laser beam scanning unit 16. The laser beam scanning section 16 comprises a laser light source 1, a pair of rotary reflecting mirrors 2 and 3, a pair of galvano scanners 4 and 5, and a screen 6, as shown in FIG.

The personal computer 8 includes a frame buffer memory unit 9 for recording bitmap information as two-dimensional bitmap data, an extraction unit 10 for extracting predetermined one-stroke data from the bitmap data, and compression processing of one-stroke data to create dot data. Dot data processing creation unit 11
And a D / A converter 12 that converts dot data into analog data and outputs the analog data to the laser beam scanning unit 16.

A secondary storage device such as a hard disk device 13 is connected to the frame buffer memory unit 9 and the dot data processing creating unit 11 of the personal computer 8, and stores bitmap data, dot data, and programs for operating the personal computer 8. Save. A display device 14 composed of a cathode ray tube or the like is connected to the personal computer 8, and visually displays and monitors bitmap data and single-stroke data as necessary. A pointing device 15 composed of a mouse, a tablet or a trackball is connected to the one-stroke data extraction unit 10 of the personal computer 8 and monitors a picture displayed on the display device 14 while monitoring a predetermined laser as a basis of the one-stroke data. A beam spot luminous path, that is, a line pattern and a predetermined path direction are designated and input.

Next, the operation of this embodiment will be described with reference to FIGS. First, the bitmap information sent from the television camera 7 is input to a frame buffer memory unit 9 included in a CPU such as a personal computer 8 and recorded as digitized two-dimensional bitmap data. The bitmap data is stored in the secondary storage device 13 as needed.

Next, based on the bitmap data, predetermined one-stroke data is extracted and designated by the extracting unit 10 in the CPU. This processing is performed by a semi-manual operation using the display device 14 and the tablet 15, and includes preprocessing of the bitmap data. First, as shown in FIG. 3, noise bits included in the bitmap data are removed. In this process, the CPU detects noise bits and automatically removes them. Also, as shown in FIG. 4, when it is determined by the monitor of the display device 14 that there is a missing portion in the bitmap data, the pointing device 15 is operated to manually designate and input the missing portion to shape the bitmap data. I do. Of course, this shaping process
Can also be automated.

At the stage where the above preprocessing is completed, the thinning process of the thick two-dimensional pattern represented by the bitmap data is performed as shown in FIG. 5, and a predetermined thin line pattern is defined. The thin line pattern is represented by a continuous point coordinate group and specifies a scanning path of the laser beam. At this time, in order to enable one-stroke scanning of the laser beam, stroke order data is designated and input by the pointing device 15, and one-stroke data is created by using this and the continuous point coordinate group.

In some cases, as shown in FIG. 6, the outline of a thick pattern may be extracted to create a thinned pattern. In this case, in addition to the route or stroke order data, since the inner contour and the outer contour are separated, it is necessary to specify and input a pair of jumping point coordinates for connecting the two in a single stroke.

Next, as shown in FIG. 7, the continuous point coordinate group constituting the one-stroke data is compressed by the dot data processing creating unit 11 and converted into discontinuous dot data. At this time, the process creation unit 11
Is used to identify the corner portion A and the curved portion B of the thin line pattern, and to store the point coordinates existing in these portions relatively densely and the point coordinates existing in other straight line portions relatively coarsely. Compressed.

The dot data processing creation unit 11 also has a function of finally adjusting the obtained dot data and performing a colorization process. Actually, the obtained dot data is sent to the laser beam scanning unit 16, and final adjustment and coloring processing are performed while monitoring the laser graphic display. The adjusted dot data is stored in the secondary storage device 13.

Finally, after the dot data is sent to the D / A converter unit 12 of the CPU and converted into an analog signal, it is repeatedly output to the laser beam scanning unit 16 at high speed in a time series according to the specified stroke order, amplified, and then driven by the galvano scanner Then, the laser beam is scanned in accordance with a predetermined thin line pattern to reproduce an image.

Now, referring to the flowcharts of FIGS. 8 (A) and 8 (B), a dot data processing creating unit which is a characteristic part of the present invention
The operation of 11 will be described in more detail. In step 101, the one-stroke data stored in the primary and secondary storage device is read into the CPU. In step 102, all jump point coordinates included in the one-stroke data are identified and recorded. Steps
In 103, the point coordinates to be subjected to the compression processing (hereinafter referred to as target point coordinates) are set as the first point coordinates in one-stroke drawing. In step 104, it is determined whether or not the point-of-interest coordinates match the first point coordinates. If they match, the process jumps to step 113 to move the point of interest coordinates to the next point. If they do not match, the process proceeds to step 105.

In step 105, it is determined whether or not the point of interest matches any of the recorded jump points. If they match, in step 106, the waiting time assigned to the point of interest is lengthened and set as "jump point waiting time". By this processing, the jumping part of the one-stroke graphic display is emphasized, and a clearer display can be obtained. Thereafter, the process jumps from step 106 to step 113 to move the point of interest to the next point.

On the other hand, if it is determined in step 105 that the point of interest is not a jump point, the process proceeds to step 107. step 1
In step 07, a difference vector vf between the point of interest and the point before it and a difference vector vb between the point of interest and the next point are calculated. Next, at step 108, the cross product R of the two difference vectors vf and vb is calculated.
Is calculated. The value of the outer product R represents the curvature of the line pattern near the point of interest. Next, at step 109, it is determined whether or not the absolute value | R | of the calculated cross product R is larger than a predetermined cross product limit value. If the target point is larger than the outer product limit value, the point of interest is determined to be present at a corner portion or a curved portion of the line pattern, and is left as it is and is not deleted. That is, after step 109, the process jumps to step 113 and proceeds to the processing of the next new point of interest.

On the other hand, if the cross product absolute value | R | is smaller than the set cross product limit value in step 109, it is determined that the point of interest exists in the straight line portion of the line pattern, and the process proceeds to step 110. step 1
At 10, the distance d between the point of interest and the next point is calculated. Next, it is determined whether or not the value of d calculated in step 111 is larger than a preset inter-dot distance limit value. If it is determined that the distance d is larger than the limit value, the process jumps to step 113 without doing anything and enters the processing of the next point of interest. This operation prevents the point coordinates from being unnecessarily deleted from the straight line portion.

On the other hand, if the distance d is smaller than the set limit value,
The flow shifts to 112, where the target point coordinates are deleted, and the data is compressed.

Next, the process proceeds to step 113, where the next point is selected as a new point of interest. In step 114, it is determined whether or not the new point of interest is the last dot in one-stroke drawing. If it is not the last dot, the process returns to step 104 to repeat the above-described loop processing including the series of steps 104 to 114, and performs compression processing for all dots on the line pattern.

On the other hand, when it is determined in step 114 that the new point of interest is the last point of one-stroke writing, the process proceeds to step 115. Here, it is determined whether or not the point coordinates during the loop processing described above have never been deleted. If it is determined that the deletion of the point coordinates has never been performed, the data compression is already performed to the limit, and further deletion of the dot data is not desired, and the process proceeds to step 116. Here, the finally determined dot data is output from the CPU to the secondary storage device and written.

On the other hand, if the point coordinates have been deleted at least once in the loop processing, a step 10 is executed to perform the compression processing loop again.
Return to 3.

With this processing, compression of one-stroke data is automatically
This is performed in U, and the dot data density of the corner portion and the curved portion of the line pattern becomes relatively high, and the dot data density of the straight line portion becomes relatively low. In addition, jumping dots are emphasized.

〔The invention's effect〕

As described above, according to the present invention, one-stroke data such as a laser graphic display can be automatically compressed by using a computer such as a personal computer to obtain vectorized data, that is, dot data. Conventionally, compression processing of one-stroke data is performed manually, and creation of dot data is a task that requires skill and is a relatively time-consuming task, but by using this system, even an unskilled person can use this system. There is an effect that dot data can be created easily and in a single time.

Since arbitrary two-dimensional bitmap data stored in a secondary storage device can be used as an original image used for creating dot data, continuously changing moving images such as animations can be converted into dot data.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of a laser graphic display device according to the present invention, FIG. 2 is a perspective view showing a detailed configuration of a laser beam scanning unit shown in FIG. 1, and FIG. FIG. 4 is a schematic diagram for explaining bitmap data noise removal processing performed by the CPU shown in FIG.
FIG. 5 is a schematic diagram showing a bitmap data correction process similarly performed by the CPU, FIG. 5 is a schematic diagram showing a thinning process of a thick pattern also performed by the CPU, and FIG.
FIG. 7 is a schematic diagram showing a contour pattern extraction process of a thick pattern performed in FIG. 7, FIG. 7 is a schematic diagram showing a compression process of one-stroke data performed by the CPU, and FIGS. ) Is
9 is a flowchart for explaining compression processing of one-stroke data and creation processing of dot data performed by the CPU. Reference numerals 1 are a laser light source, 2 and 3 are a pair of rotary reflecting mirrors, 4 and 5 are galvano scanners, 6 is a screen, 7 is a TV camera, 8 is a personal computer, 9 is a frame buffer memory unit, and 10 is A one-stroke data extraction unit, 11 is a dot data processing creation unit, 12 is a D / A converter, 13 is a hard disk drive, 14 is a laser beam scanning unit, 15 is a pointing device, and 16 is a laser beam scanning unit.

Claims (3)

(57) [Claims] 1. A frame memory for recording bitmap data obtained by digitizing two-dimensional image information, a single-point writing including continuous point coordinate data specifying a predetermined line pattern from the bitmap data and data specifying a stroke order thereof In a laser graphic display device comprising an extraction unit for extracting data and a laser beam scanning unit for repeatedly scanning a laser beam at high speed in accordance with one-stroke data and visually reproducing a line pattern on a screen, A processing creation unit for compressing one-stroke data and creating discontinuous dot data by deleting more point coordinates existing in the linear part of the line pattern and deleting less point coordinates existing in the corner part and the curved part And outputs the discontinuous dot data to the laser beam scanning unit repeatedly in a time-series manner. Laser Guraffikku display device according to claim to perform live. 2. The processing creating section calculates a difference vector vf between a target point coordinate to be processed and a previous point coordinate and a difference spectrum vb between a target point coordinate and a next point coordinate, and calculates an outer product of the two vectors. 2. The laser graphic display device according to claim 1, further comprising an identification unit for determining a curvature of the line pattern in the vicinity of a point of interest based on the obtained value. 3. The processing creating section calculates a distance between a point coordinate of interest and the next point coordinate when the obtained cross product is smaller than a set cross product limit value. The laser graphic display device according to claim 2, further comprising a deletion unit that deletes point coordinates.