Shutter glasses and related 3D display system

The present invention discloses shutter glasses and a 3D display system. The shutter glasses include a first polarizer, a second polarizer, a normally-white LCD panel, and a normally-black LCD panel. A thickness of the normally-white LCD panel is not the same as a thickness of the normally-black LCD panel, and an optical compensation film is installed between the first polarizer and the liquid crystal layer of the normally-black LCD panel and/or between the second polarizer and the liquid crystal layer of the normally-black LCD panel in order to compensate for a dispersion occurred when the liquid crystal layer of the normally-black LCD panel is in a dark mode. In this way, the present invention can not only shorten the response time of the shutter glasses to reduce the power consumption, but also reduce the 3D crosstalk.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to display techniques, and more particularly, to a shutter glasses and a 3D display system.

2. Description of the Prior Art

In the age of high-definition TV, a 3D mode has become a preferred function of a big-size TV. In general, specific glasses are required when a user watches the 3D image on the 3D TV. The 3D TVs can be categorized into two categories, shutter-type 3D TV and polarization-type 3D TV.

The shutter-type 3D TV requires a shutter glasses having an LCD having a 120 Hz or higher refresh rate to show the 3D images. The basic theory of the shutter glasses is: When a left-eye image is being shown, the right-eye of the shutter glasses is closed, and when a right-eye image is being shown, the left-eye of the shutter glasses is closed. In this way, the left-eye images and the right-eye images can be separately viewed by single eye such that the user can feel the 3D effect.

Currently, the shutter glasses often utilize a twisted nematic type (TN type) LCD panel. Please refer toFIG. 1, which is a diagram showing a response waveform of shutter glasses according to the related art. As shown inFIG. 1, the luminance of the shutter glasses changes according to the variance of the input voltage of the LCD panel. Furthermore, the rising time (Tr) and the falling time (Tf) are not the same. FromFIG. 1, it can be seen that the rising time (Tr) is shorter than the falling time (Tf), and the falling time (Tf) is double to triple of the rising time (Tr). Therefore, this often introduces a 3D motion blur and a luminance insufficiency of the 3D image. In order to avoid aforementioned problems, two solutions are often used. The first solution is to time-interleavingly turn on the backlight for preventing the liquid crystals from being responded incompletely. The second solution is to raise the luminance of the LCD panel for compensating for the luminance insufficiency of the 3D images.

Unfortunately, these two solutions consume more power and raise the manufacturing cost of the LCD panel.

SUMMARY OF THE INVENTION

It is therefore one of the primary objectives of the present invention to provide a shutter glasses and a 3D display system, to reduce power consumption and 3D crosstalk.

According to an exemplary embodiment of the present invention, a shutter glasses comprises a frame, a liquid crystal display panel installed inside the frame, a first polarizer, and a second polarizer. The liquid crystal display panel comprises a normally-white LCD panel and a normally-black LCD panel. A thickness of the normally-white LCD panel is not the same as a thickness of the normally-black LCD panel. The first polarizer is installed between the normally-white LCD panel and the normally-black LCD panel. The normally-black LCD panel comprises a first substrate and a second substrate. A liquid crystal layer of the normally-black LCD panel is sandwiched between the first substrate and the second substrate. The first substrate is close to the first polarizer, and the second substrate is close to the second polarizer. The optical compensation film is installed between the first substrate and the first polarizer and/or between the second substrate and the second polarizer in order to compensate for a dispersion occurred when the liquid crystal layer of the normally-black LCD panel is in a dark mode. A thickness of the optical compensation film is determined according to a variance trend of the dispersion of the liquid crystal layer of the normally-black LCD panel, and the thickness is determined to be thicker when the variance trend is larger.

In one aspect of the present invention, the optical compensation film is made by a material selected from a group consisting of acetate fiber (TAC), cycloalkene polymer (COC), cycloalkene copolymer (COP), and thermoplastic polyester (PET).

According to an exemplary embodiment of the present invention, a shutter glasses comprises a frame, a liquid crystal display panel installed inside the frame, a first polarizer, and a second polarizer. The liquid crystal display panel comprises a normally-white LCD panel and a normally-black LCD panel. A thickness of the normally-white LCD panel is not the same as a thickness of the normally-black LCD panel. The first polarizer is installed between the normally-white LCD panel and the normally-black LCD panel. A liquid crystal layer of the normally-black LCD panel is installed between the first polarizer and the second polarizer. An optical compensation film is installed between the first polarizer and the liquid crystal layer of the normally-black LCD panel and/or between the second polarizer and the liquid crystal layer of the normally-black LCD panel in order to compensate for a dispersion occurred when the liquid crystal layer of the normally-black LCD panel is in a dark mode.

In one aspect of the present invention, a thickness of the optical compensation film is determined according to a variance trend of the dispersion of the liquid crystal layer of the normally-black LCD panel, and the thickness is determined to be thicker when the variance trend is larger.

In another aspect of the present invention, the normally-black LCD panel comprises a first substrate and a second substrate. The liquid crystal layer is sandwiched between the first substrate and the second substrate. The first substrate is close to the first polarizer, the second substrate is close to the second polarizer. The optical compensation film is installed between the first substrate and the first polarizer and/or between the second substrate and the second polarizer.

In another aspect of the present invention, the normally-black LCD panel comprises a first substrate and a second substrate. The liquid crystal layer is sandwiched between the first substrate and the second substrate. The first substrate is close to the first polarizer, and the second substrate is close to the second polarizer. The optical compensation film is installed between the first substrate and the liquid crystal layer and/or between the second substrate and the liquid crystal layer.

In another aspect of the present invention, the shutter glasses further comprises a third polarizer. The normally-white LCD panel is between the first polarizer and the third polarizer. An optical axis of the second polarizer is parallel to an optical axis of the first polarizer, and an optical axis of the third polarizer is perpendicular to the optical axis of the first polarizer.

In another aspect of the present invention, the optical compensation film is made by a material selected from a group consisting of acetate fiber (TAC), cycloalkene polymer (COC), cycloalkene copolymer (COP), and thermoplastic polyester (PET).

In another aspect of the present invention, the shutter glasses further comprises an incident side and an emitting side. The normally-black LCD panel is located on the incident side and the normally-white LCD panel is located on the emitting side.

In still another aspect of the present invention, the shutter glasses further comprises an incident side and an emitting side. The normally-black LCD panel is located on the emitting side and the normally-white LCD panel is located on the incident side.

In yet another aspect of the present invention, the shutter glasses further comprises a driving circuit, configured to generate a driving signal to drive the LCD panel.

According to an exemplary embodiment of the present invention, a 3D display system comprises a shutter glasses. The shutter glasses comprise a frame, a liquid crystal display panel installed inside the frame, a first polarizer, and a second polarizer. The liquid crystal display panel comprises a normally-white LCD panel and a normally-black LCD panel. A thickness of the normally-white LCD panel is not the same as a thickness of the normally-black LCD panel. The first polarizer is installed between the normally-white LCD panel and the normally-black LCD panel. A liquid crystal layer of the normally-black LCD panel is installed between the first polarizer and the second polarizer. An optical compensation film is installed between the first polarizer and the liquid crystal layer of the normally-black LCD panel and/or between the second polarizer and the liquid crystal layer of the normally-black LCD panel in order to compensate for a dispersion occurred when the liquid crystal layer of the normally-black LCD panel is in a dark mode.

In one aspect of the present invention, a thickness of the optical compensation film is determined according to a variance trend of the dispersion of the liquid crystal layer of the normally-black LCD panel, and the thickness is determined to be thicker when the variance trend is larger.

In another aspect of the present invention, the normally-black LCD panel comprises a first substrate and a second substrate. The liquid crystal layer is sandwiched between the first substrate and the second substrate. The first substrate is close to the first polarizer, the second substrate is close to the second polarizer. The optical compensation film is installed between the first substrate and the first polarizer and/or between the second substrate and the second polarizer.

In another aspect of the present invention, the normally-black LCD panel comprises a first substrate and a second substrate. The liquid crystal layer is sandwiched between the first substrate and the second substrate. The first substrate is close to the first polarizer, and the second substrate is close to the second polarizer. The optical compensation film is installed between the first substrate and the liquid crystal layer and/or between the second substrate and the liquid crystal layer.

In another aspect of the present invention, the shutter glasses further comprises a third polarizer. The normally-white LCD panel is between the first polarizer and the third polarizer. An optical axis of the second polarizer is parallel to an optical axis of the first polarizer, and an optical axis of the third polarizer is perpendicular to the optical axis of the first polarizer.

In another aspect of the present invention, the optical compensation film is made by a material selected from a group consisting of acetate fiber (TAC), cycloalkene polymer (COC), cycloalkene copolymer (COP), and thermoplastic polyester (PET).

In another aspect of the present invention, the shutter glasses further comprises an incident side and an emitting side. The normally-black LCD panel is located on the incident side and the normally-white LCD panel is located on the emitting side.

In still another aspect of the present invention, the shutter glasses further comprises an incident side and an emitting side. The normally-black LCD panel is located on the emitting side and the normally-white LCD panel is located on the incident side.

In yet another aspect of the present invention, the shutter glasses further comprises a driving circuit, configured to generate a driving signal to drive the LCD panel.

In contrast to the related art, the present invention installs stacked normally-white LCD panel and normally-black LCD panel in the shutter glasses. Furthermore, the present invention installs an optical compensation film between the first polarizer and the liquid crystal layer of the normally-black LCD panel or/and between the second polarizer and the liquid crystal layer of the normally-black LCD panel. In this way, the present invention is able to compensate for the dispersion when the normally-black LCD panel is in a dark mode such that the 3D crosstalk is reduced. Moreover, the present invention installed the normally-white LCD panel and the normally-black LCD panel having different thicknesses. This makes the response time of the shutter glasses respectively equal to the voltage rising time of the normally-white LCD panel and the normally-black LCD panel. Therefore, the response time of the shutter glasses is shorten such that a purpose of lower the power consumption can be achieved.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Please refer toFIG. 2, which is a diagram showing a structure of shutter glasses according to a first embodiment of the present invention. As shown inFIG. 2, the shutter glasses20comprise a frame21, legs22, LCD panels23, and a driving circuit27. The legs22are used to support the frame21. The frame21is used to support the LCD panels23, which are utilized as lens. The driving circuit27is installed on the legs and is used to generate a driving signal to drive the LCD panels23. Furthermore, the driving signal is optimized as a square wave signal.

Please refer toFIG. 3, which is a diagram showing a part of the shutter glasses20shown inFIG. 2. InFIG. 3, the LCD panel23comprises a normally-white LCD panel231and a normally-black LCD panel232. The thickness of the normally-black LCD panel232is not the same as the thickness of the normally-white LCD panel231.

The shutter glasses20further comprises a first polarizer24, a second polarizer25, and a third polarizer26. The normally-white LCD panel231comprises a liquid crystal layer235. The normally-black LCD panel232comprises a liquid crystal layer234. The first polarizer24is installed between the normally-white LCD panel231and the normally-black LCD panel232. The liquid crystal layer234of the normally-black LCD panel232is installed between the first polarizer24and the second polarizer25. The normally-white LCD panel231is between the third polarizer26and the first polarizer24. An optical compensation film is installed between the second polarizer25and the liquid crystal layer234of the normally-black LCD panel232in order to compensate for the dispersion when the liquid crystal layer234of the normally-black LCD panel232is in a dark mode.

Specifically, the normally-black LCD panel232further comprises a first substrate236and a second substrate237. The first substrate236is close to the first polarizer24. The second substrate237is close to the second polarizer25. The liquid crystal layer234is between the first substrate236and the second substrate237. In this embodiment, the optical compensation film233is installed between the second polarizer25and the second substrate237.

In this embodiment, the thickness of the optical compensation film233is determined according to the variance trend of the dispersion of the liquid crystal layer234of the normally-black LCD panel232. Specifically, if the variance trend of the dispersion of the liquid crystal layer234is larger, the variance trend of the dispersion of the optical compensation film233is larger. Therefore, the thickness is determined to be thicker. However, once the material for manufacturing the liquid crystal layer234is determined, the variance trend of the dispersion of the liquid crystal layer234is determined. Therefore, the variance trend of the dispersion can firstly be evaluated according to the material of the liquid crystal layer234of the normally-black LCD panel232. And then, the thickness of the optical compensation film233can then be determined correspondingly according to the variance trend of dispersion of the liquid crystal layer234such that the optical compensation film233can be designed to compensate for the dispersion phenomenon.

In this embodiment, the optical compensation film233is a compensation film having multiple optic axes. It means that the optical compensation film233has multiple refraction rates along different optic axes. The main material for manufacturing the optical compensation film233includes one or the combination of acetate fiber (TAC), cycloalkene polymer (COC), cycloalkene copolymer (COP), and thermoplastic polyester (PET).

After the optical compensation film233is installed, the thickness of the normally-black LCD panel232is then adjusted. The adjustment procedure is: providing a composite light source to the normally-black LCD panel232, which is in the normal phase, and then adjusting the thickness of the normally-black LCD panel232until the phase difference (Δnd) of the lights having different wavelengths can maintain a fixed value after the lights having different wavelengths pass through the normally-black LCD panel232and the optical compensation film.

Please refer toFIG. 4, which is a diagram showing a relationship between the waveform and a dispersion trend. Because the optical compensation film233compensates for the dispersion due that the lights having different wavelengths pass through the liquid crystal layer234, this makes the phase difference (Δnd) maintain a fixed value, and the phases of the lights having different wavelengths λ are rotated by 90 degrees after the lights pass through the normally-black LCD panel232. At this time, the transmittance of the normally-black LCD panel232is the lowest. As is known, the normal phase of the normally-black LCD panel232is the dark mode, and the normal phase of the normally-white LCD panel231is the bright mode. Therefore, the lowest transmittance of the normally-black LCD panel232can reduce 3D crosstalk of the shutter glasses20.

Please note, after the optical compensation film233is installed inside the shutter glasses20, in order to guarantee the lowest transmittance of the normally-black LCD panel232, the thickness of the normally-black LCD panel232is adjusted to be different from the thickness of the normally-white LCD panel231. In addition, the present invention does not limit the thickness of the normally-black LCD panel232. The thickness of the normally-black LCD panel232can be adjusted as long as it can guarantee that the normally-black LCD panel232has the lowest transmittance.

In this embodiment, the shutter glasses20further comprises an incident side S1 and an emitting side S2. Please note, the normally-white LCD panel231is installed on the incident side S1, and the normally-black LCD panel232is installed on the emitting side S2.

In another embodiment, the normally-black LCD panel232is installed on the incident side S1, and the normally-white LCD panel231is installed on the emitting side S2.

Please refer toFIG. 5, which is a diagram showing a part of the shutter glasses according to a second embodiment of the present invention. The difference between the shutter glasses50and the shutter glasses20of the first embodiment is: the optical compensation film533of the shutter glasses50is installed between the first polarizer54and the first substrate536.

Similarly, the optical compensation film533can also compensate for the dispersion when the liquid crystal layer534of the normally-black LCD pane532is the dark mode.

Please refer toFIG. 6, which is a diagram showing a part of the shutter glasses according to a third embodiment of the present invention. The difference between the shutter glasses60and the shutter glasses20of the first embodiment is: the shutter glasses60comprise a first optical compensation film633aand a second optical compensation film633b. The first optical compensation film633ais installed between the first polarizer64and the first substrate636, and the second optical compensation film633bis installed between the second polarizer65and the second substrate637.

Please note, in the condition that the material and producing method of the optical compensation film is similar and the normally-black LCD panel has similar dispersion trend, the first optical compensation film633aand the second optical compensation film633bhas a thinner thickness than the optical compensation film233of the first embodiment.

Similarly, the first optical compensation film633aand the second optical compensation film633bcan also compensate for the dispersion when the liquid crystal layer634of the normally-black LCD pane632is the dark mode.

Please refer toFIG. 7, which is a diagram showing a part of the shutter glasses according to a fourth embodiment of the present invention. The difference between the shutter glasses70and the shutter glasses20of the first embodiment is: the optical compensation film733of the shutter glasses70is installed between the second substrate737and the liquid crystal layer734of the normally-black LCD panel732. Specifically, the normally-black LCD panel732further comprises a first transparent electrode738and a second transparent electrode739. The first transparent electrode738is installed between the first substrate736and the liquid crystal layer734. The first transparent electrode739is installed between the second substrate737and the liquid crystal layer739.

In another embodiment, the optical compensation film733can be installed between the first substrate736and the first transparent electrode738. Or, there are two optical compensation films733, which are respectively installed between the first substrate736and the first transparent electrode738and between the second substrate737and the second transparent electrode739.

Please refer toFIG. 8, which is a diagram showing a part of the shutter glasses according to a fifth embodiment of the present invention. The difference between the shutter glasses80and the shutter glasses70of the fourth embodiment is: the optical compensation film833and the second polarizer85are both installed between the second substrate837and the second transparent electrode839, where the optical compensation film833is close to the second transparent electrode839and the second polarizer85is close to the second substrate837.

In another embodiment, the optical compensation film833and the first polarizer84are both installed between the first substrate836and the first transparent electrode838, where the optical compensation film833is close to the first transparent electrode838and the first polarizer84is close to the first substrate836. Or, there are two optical compensation films833. One compensation films833and the first polarizer84are installed between the first substrate836and the first transparent838. The other compensation film833and the second polarizer85are installed between the second substrate837and the second transparent electrode839.

Please note, the operation principle of the shutter glasses20of the first embodiment shown inFIG. 2andFIG. 3will be illustrated in the following disclosure.

Please refer toFIG. 9in conjunction withFIG. 3.FIG. 9is a diagram showing a response waveform of the shutter glasses according to the present invention. As shown inFIG. 9, the voltage signals V0, V1, and V2are used for driving the normally-white LCD panel231and the voltage signals V3, V4, and V5are used for driving the normally-black LCD panel232. These voltages signals V0-V5are provided by the driving circuit27shown inFIG. 2.

In this embodiment, the optical axis of the second polarizer25is parallel to the optical axis of the first polarizer24, and the optical axis of the third polarizer26is perpendicular to the optical axis of the first polarizer24. The LCD panel23is a TN-type LCD panel. When there is no voltage applied to the normally-white LCD panel231(the voltage V0is 0), the polarization of light passing through the second liquid crystal layer235is rotated by 90 degrees relative to that of the light passing through the third polarizer26, i.e. the polarization direction of the light passing through the second liquid crystal layer235is parallel to the optical axis of the first polarizer24. Therefore, the light can pass through the normally-white LCD panel231and the normally-white LCD panel231is in the bright mode. When the voltage changes from V0to V1or V2, the liquid crystals of the normally-white LCD panel231are arranged perpendicularly. At this time, the second liquid crystal layer235does not rotate. Therefore, the normally-white LCD panel is in the dark mode.

Correspondingly, when there is no voltage inputted to the normally-black LCD panel232(the voltage V3is 0), the polarization of light passing through the first liquid crystal layer234is rotated by 90 degrees relative to that of the light passing through the first polarizer24, i.e. the polarization direction of the light passing through the first liquid crystal layer234is perpendicular to the optical axis of the first polarizer25. Therefore, the light cannot pass through the normally-black LCD panel232and the normally-black LCD panel232is in the dark mode. When the voltage changes from V3to V4or V5, the liquid crystals of the normally-black LCD panel232are arranged perpendicularly. At this time, the first liquid crystal layer234does not rotate. Therefore, the normally-white LCD panel is in the bright mode.

Please note, when there is no voltage inputted to the normally-black LCD) panel232, the optical compensation film233compensates for the dispersion of the normally-black LCD panel232such that the transmittance of the normally-black LCD panel232becomes the lowest and the 3D crosstalk is reduced.

The bright/dark condition of the shutter glasses20is determined by both the voltage of the normally-white LCD panel231and the voltage of the normally-black LCD panel232. A period of the bright/dark condition of the shutter glasses20will be illustrated in the following disclosure.

Basic condition: The voltage of the normally-white LCD panel231is the voltage V0, and the voltage of the normally-black LCD panel232is the voltage V3. At this time, the lights can pass through the normally-white LCD panel231but cannot pass thorough the normally-black LCD panel232. Therefore, at this time, the shutter glasses are in the dark mode.

From the dark mode to bright mode: The voltage of the normally-white LCD panel231is still the voltage V0. The normally-white LCD panel231is in the bright mode. The voltage of the normally-black LCD panel232rises from the voltage V3to the voltage V4. Therefore, the light can pass through the normally-black LCD panel232, and the normally-black LCD panel232is in the bright mode. Therefore, the shutter glasses are in the bright mode. Furthermore, at this time, the response time Tr of the shutter glasses is the time duration when the voltage of the normally-black LCD panel232rises from the voltage V3to V4.

From the bright mode to dark mode: The voltage of the normally-white LCD panel231rises from the voltage V0to the voltage V1. At the same time, the voltage of the normally-black falls from the voltage V4to the voltage V3. Therefore, the light cannot pass through the normally-white LCD panel231and the normally-black LCD panel232. The shutter glasses changes from the bright mode to the dark mode. The response time Tf of the shutter glasses is the time duration when the voltage of the normally-white LCD panel231rises from the voltage V0to the voltage V1.

It can be understood that the falling time of the voltage of the normally-black LCD panel232is longer than the rising time of the voltage of the normally-white LCD panel231. But, after the rising time of the voltage of the normally-white LCD panel231, the light cannot pass through the normally-white LCD panel231. Therefore, at this time, even the voltage of the normally-black LCD panel232is still falling, the normally-white LCD panel231is able to block the light and no light pass through the normally-black LCD) panel232.

Because the rising time of the voltage of the normally-white LCD panel231is the same as that of the normally-black LCD panel232, the response time of the shutter glasses20is the same. That is, Tr=Tf. Furthermore, an entire period of the response time of the shutter glasses20is the sum of the rising time of the normally-white LCD panel231and the rising time of the normally-black LCD panel232. In the related art, an entire period of the response time of the shutter glasses is the sum of the rising time and the falling time of the voltage of the LCD panel. In contrast to the related art, the present invention shutter glasses20needs less time. Therefore, the present invention can reduce the power consumption and reduce the cost.

Please note, the operation principle of the shutter glasses of the second, third, fourth, and fifth embodiments are the same as that of the first embodiment, and further illustration is omitted here.

Please refer toFIG. 10, which is a diagram showing a 3D display system according to the present invention. The 3D display system100comprises a 3D display101and shutter glasses102. The 3D display101provides a display image to the shutter glasses102. The shutter glasses102make the display image have the 3D effect. Please note, the shutter glasses102is the shutter glasses of the first to fifth embodiments, and further illustration is omitted here.

To sum up, the present invention installs stacked the normally-white LCD panel and the normally-black LCD panel having different thickness in the shutter glasses. Furthermore, an optical film is installed between the first polarizer and the liquid crystal layer of the normally-black LCD panel and/or the second polarizer and the liquid crystal layer of the normally-black LCD panel to compensate for the dispersion when the normally-black LCD panel is in the dark mode. In addition, after installing the optical compensation film, the present invention adjusts the thickness of the normally-black LCD panel such that the transmittance of the normally-black LCD panel can be the lowest in the dark mode and the 3D crosstalk is reduced.

Moreover, the present invention installs stacked the normally-white LCD panel and the normally-black LCD panel such that the response time of the shutter glasses is respectively equal to rising time of the voltage of the normally-white LCD panel and the rising time of the voltage of the normally-black LCD panel. Therefore, the response time of the shutter glasses is reduced and the power consumption is reduced.