KR20120099845A - A laser projector and a method of processing a signal thereof - Google Patents

Abstract

PURPOSE: A laser projector and a signal processing method thereof are provided to form a protection area for an eye protection according to a size change of a screen except for an initial set area and to reduce energy consumption by projecting infrared rays on a partial area and cutting off a proper power supply. CONSTITUTION: A laser projector comprises an infrared ray light source, a plurality of laser light sources(300), a first mirror, a second mirror, a scanner(500), and a controlling unit. The infrared ray light source generates infrared rays. The first mirror reflects the generated infrared rays. The second mirror reflects the infrared rays by reflecting and becoming incident and laser lights becoming incident with the scanner and transmits the same. The scanner scans the infrared rays becoming incident and laser lights on a screen. If the scanned infrared lights are located in a predetermined are within a blank area except for an image projection area on the screen, the controlling unit cuts off a power supply of an infrared ray light source. [Reference numerals] (AA) Blank image area; (BB) Images on a screen

Description

Laser projector and a method of processing a signal

The present invention relates to a laser projector, and more particularly, to a laser projector using a scanner and a signal processing method thereof.

In general, a laser projector is a system for displaying an image by projecting the input image signal on the screen by using the laser light emitted from the laser light source, mainly presentation of the conference room, projector in the theater, home of the home It is used for the implementation of a theater.

Such a laser projector may include a laser light source, a light modulator, an optical system, an optical scanner, an image controller, and the like.

Here, the laser light source includes a red laser that generates red light, a green laser that generates green light, and a blue laser that generates blue light.

The laser light source emits the generated laser light to the light modulator, and the light modulator modulates the incident laser light according to the image control signal of the image controller to generate diffracted light and emit the light to the optical system.

Subsequently, the generated diffracted light is transmitted to the optical scanner through an optical system, and the optical scanner displays the image by scanning the light while rotating the mirrors at a predetermined angle according to the mirror control signal of the image controller.

An object of the present invention is to provide a signal processing method and a laser projector in a laser projector for eye protection.

One example of a laser projector according to the present invention includes an infrared light source for generating infrared light; A plurality of laser light sources for generating laser light; A first mirror reflecting the generated infrared rays; A second mirror for reflecting and transmitting the reflected infrared rays and each incident laser light to a scanner; A scanner including an incident infrared ray and a third mirror for scanning each laser light on a screen; And a control unit which controls to cut off power supply of the infrared light source when the scanned infrared rays are not located in a predetermined area in a blank area other than the image projection area on the screen.

Here, the predetermined area may be the center and the edge of the blank area.

The laser projector may have a protection area adaptive to the size of the screen formed by the laser light by irradiating infrared rays through the scanner only to the predetermined area on the screen.

The apparatus may further include a receiver configured to receive the infrared rays reflected from the screen.

The controller may detect a distance change by using the reflection time of the infrared rays, and control to cut off power of each laser light source when the distance change is detected.

In addition, the controller may block power supply of each of the light sources in units of pixels.

The controller may block power supply to all light sources in the case of a black screen.

In addition, the laser light source and the infrared light source may be a laser diode.

The scanner may be a scanner that can be driven in at least one of two and three dimensions.

An example of a signal processing method in a laser projector according to the present invention includes: (a) generating each laser light from an infrared light and a plurality of laser light sources; (b) reflecting and transmitting the generated infrared ray and each laser light to the scanner so as to be incident; (c) scanning the incident infrared light and each laser light on a screen; And (d) controlling not to supply power to the infrared light source when the scanned infrared rays are not located in a predetermined area in a blank area other than the image projection area on the screen.

Here, the predetermined area may be the center and the edge of the blank area.

In the step (d), only the predetermined area on the screen may be irradiated with infrared rays through the scanner so as to have a protection area adaptive to the size of the screen formed by each laser light.

The signal processing method in the projector may further include (e) receiving infrared rays reflected from the screen.

In the step (d), the distance change may be detected using the reflection time of the infrared rays, and if the distance change is detected, the power of the laser light sources may be cut off.

In addition, in the step (d), the power supply of each of the light sources may be blocked on a pixel basis.

In the case of the black screen, power supply of all light sources may be cut off.

In addition, the laser light source and the infrared light source may be a laser diode.

The scanning step may be driven in at least one of two and three dimensions.

According to the present invention,

First, in addition to the initially set area, there is an effect that a protection area for eye protection may be provided adaptively in response to a change in the size of the screen.

Second, there is an effect that can reduce the power consumption by irradiating infrared only to a part of the area and cut off the appropriate power supply.

Third, when provided as a separate pixel device, more various images can be obtained, and thus the expansion is easy.

1 is a view illustrating a laser light irradiation and eye protection problems of a general laser projector;
2 is a view illustrating a laser light irradiation and an eye protection problem of a scanning laser projector;
3 is a diagram illustrating an example of a scanner having a scanning mirror according to the present invention.
4 is a diagram illustrating an example of a projector system including a laser diode (LD) and a 3D scanner according to the present invention.
5 is a view illustrating another example of a projector system including a laser diode (LD) and a three-dimensional scanner according to the present invention;
FIG. 6 is a diagram for explaining a case of detecting infrared light in a projector system in the case of a fixed type;
7 is a diagram illustrating a case of detecting infrared light in a projector system in the case of a scanner type, and
8 is a block diagram illustrating an example of a laser projector according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The present invention relates to a signal processing method for eye protection in a projector using a laser and a scanner or a laser projector of a scanning method.

Products using lasers are required to comply with safety regulations for lasers that can reach the human body.

In particular, in the case of a laser projector in connection with the present invention, the problem of human eye protection may be caused by the laser light being projected. Therefore, there are rigorous standards for eye protection, which vary slightly from country to country. For example, in Korea, KS C IEC 60825 is established to limit each product and other countries have similar regulations. These regulations stipulate that the sale of a relevant product must be made in each country only if it has passed laser safety inspections for inspection (eg inspection standards, eg IEC 60825, ANSI Z136).

In the context of the present invention, there is a brightness limitation with respect to eye protection in the case of a projector using a laser light source. For example, in IEC 60825, when it comes to eye protection, a brief look at Class 1, which means that it is safe to look at the laser for a long time, is decent, which means that it is safe to avoid. The provisions of Class 2 have been prepared and presented.

These regulations are slightly different according to the type of product, general household appliances including the projector related to the present invention can be sold to products that are targeted for Class 1 without a special warning. However, products targeted for Class 2 may be sold only if the warning text is indicated.

Hereinafter, with reference to the present invention, the contents related to eye protection in a laser projector will be described first.

1 is a view illustrating a laser light irradiation and eye protection problems of a general laser projector, and FIG. 2 is a view illustrating a laser light irradiation and eye protection problems of a scanning laser projector.

FIG. 1 is a case of a general laser projector, and FIG. 2 is a content related to eye protection, in particular, of a laser projector of a scanning method using a scanner.

In particular, in the case of the scanning method of FIG. 2, the laser light scanned on the screen is sequentially scanned from top to bottom. Hereinafter, the present invention will be described using the laser projector of the scanning method shown in FIG. 2 as an example, but the scope of the present invention is not limited thereto. Therefore, although not specifically mentioned below, the term "laser projector" is used to mean both the laser projectors of FIGS. 1 and 2.

The laser projector provides an image to a user by irradiating the screen with laser light generated from at least one laser light source for the input image signal.

However, as shown in FIGS. 1 and 2, when the user is positioned between the laser projector 100 and the screen and gazes at the irradiated laser light, eye protection problems as described above may occur.

3 is a diagram illustrating an example of a scanner having a scanning mirror according to the present invention.

Recently, a micro projector using a laser diode (LD) has been developed and spread.

3 illustrates a scanner 100 including a scanning mirror for the development of a compact projector together with the laser diode.

In the present specification, the reflective mirror may be driven in 2-dimensional or 3-dimension.

However, FIG. 3 illustrates a three-dimensional scanner including a reflection mirror driven in three dimensions.

Referring to FIG. 3, the scanner 100 may move in a vertical or horizontal direction as needed to project images of various sizes onto a screen using an angle of a desired reflection mirror.

In the projector using the scanner 100 and the laser diode LD, a laser diode (LD) light, such as a laser point (Class 2), is reflected by the scanner 100 and enters the human eye. It may damage it.

Therefore, as described above, in order to prevent such fatal damage of the eye, the projector according to the present invention is intended to have a protection system.

4 is a diagram illustrating an example of a projector system including a laser diode (LD) and a 3D scanner according to the present invention.

Referring to FIG. 4, a projector system according to the present invention may include a projector including a scanner 100, a laser diode (LD) 200, a lens 300, an IR detector 400, and a controller 600. It is configured to include a screen (500) for outputting the image.

Here, the laser diode (LD) 200 operates as a light source for signal processing on the input image via the control unit 600. The laser diode 200 is, for example, a laser diode (Blue LD) for providing a blue light for a signal relating to the image, a laser diode (Green LD) for providing a green light for a signal relating to the image, and to the image. A laser diode (Red LD) that provides red light for a related signal is illustrated, but is not necessarily limited to the laser diode described above.

The lens 300 synthesizes the laser light input from the laser diode (LD) 200.

Each laser light synthesized by the lens 300 is incident to the scanner 100.

The scanner 100 scans each incident laser light and projects it onto the screen.

In this process, the scanner 100 controls, for example, the reflection angle of the scanning reflection mirror under the control of the controller 600 so that each laser light incident on the screen is projected.

In addition, the IR detector 400 irradiates infrared rays to a predetermined specific area on the screen 500 and detects a time when the irradiated infrared rays return through the screen 500 to determine whether an obstacle, that is, the eyes of the user, is located. In operation, power supply to the laser diode 200 is cut off.

However, the projector system of FIG. 4 is a fixed protection system, and can detect only a predetermined limited space.

For example, the projector system of FIG. 4 does not cover the entire area of the screen, and turns off the power supply of the laser diode 200 only when entering the limited area or the dangerous area of the object, that is, the area where the laser light is exposed. Protect your eyes.

In the projector system of FIG. 4, the image projection area of the scanner 100 is changed from, for example, a narrow screen to a wide screen, and thus cannot be controlled for each situation such as changing from a VGA screen to a WVGA screen at the same distance. In this case, there is still no choice but to determine the existence of the object only for the originally set area.

This may eventually cause a malfunction of the projector system.

In addition, the projector system of FIG. 4 consumes a lot of power due to continuous power supply because the projector system is continuously turned on regardless of whether or not the image is output.

This may be a disadvantage in terms of power consumption, which is a big issue in the case of a portable projector or a small or small projector.

5 is a diagram illustrating another example of a projector system including a laser diode (LD) and a three-dimensional scanner according to the present invention.

Another example of a laser projector according to the present invention includes an infrared light source 800 for generating infrared rays, a plurality of laser light sources 200 for generating laser light, a first mirror 920 for reflecting the generated infrared rays, and reflected and incident light. A scanner (100) including a second mirror (910) for reflecting and transmitting the infrared rays and incident laser light to the scanner, a third mirror for scanning the incident infrared rays and each laser light on the screen, and the scanned infrared rays The control unit 600 controls to cut off the power supply of the infrared light source when it is not located in a predetermined area in a blank area other than the image projection area on the screen.

In an exemplary embodiment, the predetermined area may be the center and the edge of the blank area.

The laser projector may have a protection area adaptive to the size of a screen formed by each laser light by irradiating infrared rays through the scanner only to the predetermined area on the screen.

The laser projector according to the present invention may further include a receiver for receiving infrared rays reflected from the screen.

The controller may detect a distance change by using the reflection time of the infrared rays, and control to cut off power of each laser light source when the distance change is detected. The controller may block power supply of each of the light sources in units of pixels. In addition, the controller may control to cut off power supply of all light sources in the case of a black screen.

In addition, the laser light source and the infrared light source may be laser diodes.

The scanner may be a scanner that can be driven in at least one of two and three dimensions.

The laser projector according to the present invention first determines whether the infrared light exists only in a predetermined area of the blank area of the screen before the image on the screen is initially input, and operates only when the laser light is present in the predetermined area. Can be.

In the above description, the predetermined area includes, for example, an edge and a center of the blank area.

This process checks the safety area and information about the area, and then continuously operates in the same infrared light area.

The infrared light thus emitted is reflected on the screen (for example, a wall, a screen on which the image is projected), calculates the time to come to the infrared receiver 700, and checks the distance to the screen so that a sudden portion within the protection area is obtained. When the distance of the region is changed, a protection function may be exhibited by cutting off the power of the laser diode 200.

As such, by emitting infrared light through the scanner 100, a protection area having a size appropriate to the size change of the screen formed through the scanner 100 may be provided.

In this way, the infrared region is only partially used to reduce power consumption, and an adaptive protection region suitable for the screen may be formed even if the size of the screen changes from time to time.

In addition, in the projector system of FIG. 5, the laser light source 800 may be implemented by blocking an image LD power using a conventional IR detection function.

In other words, by configuring a pixel device (CCD, CMOS, etc.) separately from the IR receiver 700, an infrared image can be obtained. In this case, if the infrared light enters the pixel device by appropriately adjusting the rotation angle of the scanner 100, do.

Entering the pixel device may mean, for example, adjusting a rotation angle of the scanning mirror to be projected onto an area where an image is output on the screen.

FIG. 6 illustrates a case of detecting infrared light in the projector system in the case of a fixed type, and FIG. 7 illustrates a case of detecting infrared light in the projector system in the case of a scanner type.

Referring to FIG. 6, in the case of a fixed type, the projector system may project the infrared light to the second screen if the infrared light is projected and received within a range that the initial setting covers the edge of the first screen. If the object exists on the extension line of the edge of the first screen even if it is changed, it can be detected, but the actual image is output, but the presence or absence of the object is detected only by the infrared ray in the area deviating from the extension line of the edge of the first screen. can not do. Therefore, the area is exposed to laser light as it is.

In FIG. 6, '0' means that an object is detected, and '△' means that it may or may not be detected due to uncertainty of detection, and finally, 'X' does not detect at all. Means.

In contrast, FIG. 7 illustrates a case in which an infrared light is detected by a projector system in the case of a scanner type. When infrared light is projected on a screen through the scanner as illustrated in FIG. 7, the scanning reflection mirror of the scanner 100 is connected to the infrared light. Infrared light is dependent on laser light unless differential control is made between the laser lights.

That is, even when the screen is changed from the first screen to the second screen, since the infrared light is irradiated to the same area as the laser light for the changed second screen, there is no area itself, which is uncertain or impossible to detect as shown in FIG. That is, even if an image is output to a new screen area away from the previous screen area such as a screen change, the same detection effect may be always performed.

In addition, power consumption may be reduced by irradiating infrared light only when an image is output, that is, when laser light is output.

Finally, according to the present invention, a laser projector comprises: (a) generating each laser light from an infrared light and a plurality of laser light sources; (b) reflecting and transmitting the generated infrared ray and each laser light to the scanner so as to be incident; (c) scanning the incident infrared light and each laser light on a screen; And (d) controlling to cut off power supply of the infrared light source when the scanned infrared rays are not located in a predetermined area in a blank area other than the image projection area on the screen.

Here, the predetermined area may be the center and the edge of the blank area. In the step (d), only the predetermined area on the screen may be irradiated with infrared rays through the scanner so as to have a protection area adaptive to the size of the screen formed by each laser light. The signal processing method in the projector may further include (e) receiving infrared rays reflected from the screen. In the step (d), the distance change may be detected using the reflection time of the infrared rays, and if the distance change is detected, the power of the laser light sources may be cut off.

In addition, in the step (d), the power supply of each of the light sources may be blocked on a pixel basis. In the case of the black screen, power supply of all light sources may be cut off. In addition, the laser light source and the infrared light source may be a laser diode. The scanning step may be driven in at least one of two and three dimensions.

8 is a block diagram illustrating an example of a laser projector according to the present invention.

As shown in FIG. 8, the present invention provides a driving signal generator 100, a laser driver 200, a laser light source 300, a scanner driver 400, a scanner 500, a pixel position detector 600, and compensation. The value determiner 700 and the compensator 800 may be configured to be included.

Here, the laser projector according to the present invention includes a driving signal generator 610 for generating a laser driving signal for driving the laser light source 630 and a scanner driving signal for driving the scanner 650, and a driving signal generator ( The laser driving unit 620 and the scanner driving unit 640 for driving the laser light source 630 and the scanner 650 may be further configured according to the laser driving signal and the scanner driving signal generated at 610.

Here, the driving signal generator 610 receives an image signal input from an image signal output device such as a personal computer (PC) or an audio / video (A / V) system, and lasers for signal processing of the received image signal. A driving signal and a scanner driving signal for driving the scanner are generated.

The laser light source unit 630 generates laser light, and may include a plurality of light sources such as a red, green, and blue laser light source generally associated with processing of an image signal.

Accordingly, the driving signal generator 610 may generate a video signal, a horizontal synchronization signal, and a vertical synchronization signal for red (R), green (G), and blue (B) corresponding to each laser light source. Include.

In addition, the driving signal generator 610 may generate a scanner driving signal based on the horizontal synchronizing signal and the vertical synchronizing signal of the generated laser driving signal. In this case, the generated scanner driving signal may include horizontal and vertical scanner driving signals.

The laser driver 200 generates a voltage or a current for driving the laser light source 300 including a red light source, a green light source, and a blue light source according to the received laser drive signal, and the laser light source 300 is applied to the voltage. Alternatively, laser light is generated at a level corresponding to the current value.

The scanner driver 400 includes a sine wave generating circuit, a triangle wave generating circuit, a signal synthesizing circuit, and the like, and generates a driving frequency for driving the scanner 500 according to the received scanner driving signal, and the scanner 500 is horizontal. And scanning the laser light on the screen 900 by horizontal and vertical driving according to the vertical driving frequency, thereby realizing an image on the screen 900.

The scanner 650 is input to each laser light source having a different irradiation angle from each laser light source, for example, the red laser light source R, the green laser light source G, and the blue laser light source B in the laser light source unit 630. In response to the control of the scanner driver 640, and irradiates the received laser light to the screen 690 in accordance with the scanner driving signal.

In the above-described case, the driving speed of the scanner 650 traveling through each horizontal line of one frame image is different, which may cause a problem that the brightness of the displayed image is not uniform.

Accordingly, the laser projector according to the present invention may further include a pixel position detector 660, a compensation value determiner 670, and a compensator 680. Here, the laser projector according to the present invention may compensate the laser driving signal generated by the driving signal generator 610 to more uniformly correct the brightness of the output image within the same condition.

The pixel position detector 660 detects a position of a pixel corresponding to one frame image from the generated scanner driving signal. That is, the pixel position detector 660 may detect a current pixel position of an image to be displayed on the screen 690.

The compensation value determiner 670 determines a brightness compensation value corresponding to the detected pixel.

The compensator 680 detects the brightness compensation value according to the determined brightness compensation value such that the brightness compensation value gradually increases or decreases toward a pixel farther from at least one reference pixel among all pixels corresponding to each horizontal line of one frame image. A compensation signal may be generated to compensate for the laser driving signal corresponding to the pixel.

The compensation signal generated by the compensator 680 is output to the drive signal generator 610, and the drive signal generator 610 generates a compensated laser drive signal by the input compensation signal.

In addition, according to the compensated laser driving signal, the laser driver 620 drives the laser light source 630 so that the laser light source 630 may generate the compensated laser light.

Next, the scanner 650 may scan the compensated laser light on the screen 690 to provide an image having uniform brightness compensated for the brightness distortion of the image according to the speed change of the scanner 650.

According to the present invention described above, in addition to the initially set area may be provided with a protective area for eye protection adaptively in accordance with the change in the size of the screen, to reduce the power consumption by irradiating infrared light only to a partial area and blocking the proper power supply If configured as a separate pixel device, more various images can be obtained and have expandability.

Features, structures, effects, and the like described in the above embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Further, the features, structures, effects, and the like illustrated in the embodiments can be combined and modified by other persons having ordinary skill in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of illustration, It can be seen that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (18)

An infrared light source for generating infrared light;
A plurality of laser light sources for generating laser light;
A first mirror reflecting the generated infrared rays;
A second mirror for reflecting and transmitting the reflected infrared rays and each incident laser light to a scanner;
A scanner including an incident infrared ray and a third mirror for scanning each laser light on a screen; And
And a control unit which controls to cut off power supply of the infrared light source when the scanned infrared rays are not located in a predetermined area in a blank area other than an image projection area on the screen. The method of claim 1,
The predetermined area,
And a border and a center of the blank area. The method of claim 2,
The laser projector,
And a protection area adapted to a size of a screen formed by each laser light by irradiating infrared rays through the scanner only to the predetermined area on the screen. The method of claim 3,
And a receiver for receiving infrared rays reflected from the screen. The method of claim 4, wherein
The control unit,
Detect the distance change by using the reflection time of the infrared rays,
When the distance change is detected, the laser projector, characterized in that the control to cut off the power of each laser light source. The method of claim 5,
The control unit,
Laser projector, characterized in that to cut off the power supply of each light source in units of pixels. The method of claim 6,
The control unit,
If the black screen laser projector, characterized in that to cut off the power supply of all light sources. The method of claim 1,
The laser light source and the infrared light source,
A laser projector, which is a laser diode. 9. The method of claim 8,
The scanner,
A laser projector, characterized in that the scanner can be driven in at least one of two-dimensional and three-dimensional. (a) generating each laser light from infrared light and a plurality of laser light sources;
(b) reflecting and transmitting the generated infrared ray and each laser light to the scanner so as to be incident;
(c) scanning the incident infrared light and each laser light on a screen; And
(d) controlling to cut off power supply of the infrared light source when the scanned infrared rays are not located in a predetermined area in a blank area other than the image projection area on the screen. The method of claim 10,
The predetermined area,
The signal processing method of the laser projector, characterized in that the center and the edge of the blank area. The method of claim 11,
The step (d)
And irradiating infrared rays through the scanner only to the predetermined area on the screen so as to have a protection area adaptive to the size of the screen formed by the respective laser lights. The method of claim 12,
(e) receiving the infrared light reflected from the screen; signal processing method further comprising a. The method of claim 12,
The step (d)
Detect the distance change by using the reflection time of the infrared rays,
The signal processing method of the laser projector, characterized in that the control to cut off the power of each laser light source when the distance change is detected. 15. The method of claim 14,
The step (d)
Signal processing method in a laser projector, characterized in that the power supply of the light source to the pixel unit is cut off. 16. The method of claim 15,
The step (d)
If the black screen, the signal processing method in the laser projector, characterized in that to cut off the power supply of all light sources. The method of claim 10,
The laser light source and the infrared light source,
Signal processing method in a laser projector, characterized in that the laser diode. 18. The method of claim 17,
The scanning step,
Signal processing method in a laser projector, characterized in that driven in at least one of two-dimensional and three-dimensional.

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