1. Field of the Invention
The instant disclosure relates to a projection device, and more particularly to a projection device for increasing light-transmitting efficiency.
2. Description of Related Art
According to the advancement in optical and the projection display technology, digital projection devices with high pixel resolution are widely employed for briefings, meetings, conferences or trainings. They are also becoming popular for family entertainment. Potential consumers look for lightweight digital projection apparatuses with high image quality and brightness at reasonable prices.
A projector is an apparatus that projects images onto an external screen by optical projection. A projector can be classified into four categories: CRT projector, liquid crystal display (LCD) projector, digital light processing (DLP) projector, and liquid crystal on silicon (LCOS) projector, basing on the type of light valve onboard. Moreover, the LCD projector is a transmission type projector because the onboard LCD panel is pervious to light. The LCOS and the DLP projectors are reflection type projectors because their image formation bases on light reflection principles.
The LCOS projector and the LCD projector are based on similar principles. However, unlike the LCD projector in which the light source is mounted behind the LCD panel and light signals pass through the LCD panel, the LCOS projector modulates light signals emitted from a light source to a screen by an LCOS panel. In fabricating the LCOS panel, CMOS wafer is adopted as a circuit substrate and a reflection layer. Following that, a liquid crystal layer is coated and packed with a glass panel. Due to the reflective structure in the LCOS projector, light signal emitted from the light source is reflected instead of passing through the LCOS panel. Thus, the LCOS projector is a reflective projector, whereas the LCD projector is a transmissive projector. However, the light-transmitting efficiency of the projector of the prior art is not good enough.
One of the embodiments of the instant disclosure provides a projection device for increasing light-transmitting efficiency, comprising: a light-emitting unit, a light-guiding unit, an image display unit and an image projection unit. The light-emitting unit includes a first light-emitting module for generating a first predetermined light source, a second light-emitting module for generating a second predetermined light source, and a third light-emitting module for generating a third predetermined light source. The light-guiding unit includes at least one photonic crystal fiber structure, wherein the at least one photonic crystal fiber structure has a first light input terminal corresponding and adjacent to the first light-emitting module for receiving the first predetermined light source, a second light input terminal corresponding and adjacent to the second light-emitting module for receiving the second predetermined light source, a third light input terminal corresponding and adjacent to the third light-emitting module for receiving the third predetermined light source, and a light output terminal, and the first light input terminal, the second light input terminal and the third light input terminal are separated from each other. The image display unit includes at least one image display panel corresponding and adjacent to the light output terminal. The image projection unit includes at least one projection lens corresponding and adjacent to the at least one image display panel. Therefore, the first predetermined light source, the second predetermined light source and the third predetermined light source concurrently pass through the at least one photonic crystal fiber structure to form a mixed surface light source that is projected onto the at least one image display panel from the light output terminal, the surface light source is reflected by the at least one image display panel to form an image light source that is projected onto the at least one projection lens, and the image light source passes through the at least one projection lens to form an image projection light source.
Another one of the embodiments of the instant disclosure provides a projection device for increasing light-transmitting efficiency, comprising: a light-emitting unit, a light-guiding unit, a prism unit, an image display unit and an image projection unit. The light-emitting unit includes a first light-emitting module for generating a first predetermined light source, a second light-emitting module for generating a second predetermined light source, and a third light-emitting module for generating a third predetermined light source. The light-guiding unit includes at least one photonic crystal fiber structure, wherein the at least one photonic crystal fiber structure has a first light input terminal corresponding and adjacent to the first light-emitting module for receiving the first predetermined light source, a second light input terminal corresponding and adjacent to the second light-emitting module for receiving the second predetermined light source, a third light input terminal corresponding and adjacent to the third light-emitting module for receiving the third predetermined light source, and a light output terminal, and the first light input terminal, the second light input terminal and the third light input terminal are separated from each other. The prism unit includes at least one polarization beam splitting prism corresponding and adjacent to the light output terminal. The image display unit includes at least one image display panel corresponding and adjacent to one lateral side of the at least one polarization beam splitting prism. The image projection unit includes at least one projection lens corresponding and adjacent to another lateral side of the at least one polarization beam splitting prism. Therefore, the first predetermined light source, the second predetermined light source and the third predetermined light source concurrently pass through the at least one photonic crystal fiber structure to form a mixed surface light source that is projected onto the at least one polarization beam splitting prism from the light output terminal, the surface light source is reflected by the at least one polarization beam splitting prism to form a reflecting light source that is projected onto the at least one image display panel, the reflecting light source is reflected by the at least one image display panel to form an image light source that is projected onto the at least one polarization beam splitting prism, and the image light source sequentially passes through the at least one polarization beam splitting prism and the at least one projection lens to form an image projection light source.
Yet another one of the embodiments of the instant disclosure provides a projection device for increasing light-transmitting efficiency, comprising: a light-emitting unit, a light-guiding unit, an image display module and an image projection unit. The light-emitting unit includes a first light-emitting module for generating a first predetermined light source, a second light-emitting module for generating a second predetermined light source, and a third light-emitting module for generating a third predetermined light source. The light-guiding unit includes at least one photonic crystal fiber structure, wherein the at least one photonic crystal fiber structure has a first light input terminal corresponding and adjacent to the first light-emitting module for receiving the first predetermined light source, a second light input terminal corresponding and adjacent to the second light-emitting module for receiving the second predetermined light source, a third light input terminal corresponding and adjacent to the third light-emitting module for receiving the third predetermined light source, and a light output terminal, and the first light input terminal, the second light input terminal and the third light input terminal are separated from each other. The image display module is corresponding and adjacent to the light output terminal. The image projection unit includes at least one projection lens corresponding and adjacent to the image display module.
More precisely, the at least one photonic crystal fiber structure has a light-mixing section for mixing the first predetermined light source, the second predetermined light source and the third predetermined light source, a first light-guiding section divaricately extended from the light-mixing section to guide the first predetermined light source from the first light-emitting module into the light-mixing section, a second light-guiding section divaricately extended from the light-mixing section to guide the second predetermined light source from the second light-emitting module into the light-mixing section, and a third light-guiding section divaricately extended from the light-mixing section to guide the third predetermined light source from the third light-emitting module into the light-mixing section, the first light input terminal is disposed on an end of the first light-guiding section, the second light input terminal is disposed on an end of the second light-guiding section, the third light input terminal is disposed on an end of the third light-guiding section, and the light output terminal is disposed on an end of the light-mixing section.
Therefore, because the light-guiding unit includes at least one photonic crystal fiber structure disposed between the light-emitting unit and the image display unit or between the light-emitting unit and the prism unit, the light-transmitting efficiency of the projection device of the instant disclosure can be increased (i.e., the optical loss of the projection device of the instant disclosure can be decreased). In addition, the size of the projection device of the instant disclosure can be reduced due to the flexibility of the photonic crystal fiber structure.
To further understand the techniques, means and effects of the instant disclosure applied for achieving the prescribed objectives, the following detailed descriptions and appended drawings are hereby referred, such that, through which, the purposes, features and aspects of the instant disclosure can be thoroughly and concretely appreciated. However, the appended drawings are provided solely for reference and illustration, without any intention to limit the instant disclosure.
Referring to
First, referring to
For example, referring to
Moreover, referring to
More precisely, referring to
Furthermore, the image display unit 4 (i.e., an image display module) includes at least one image display panel 40 corresponding and adjacent to the light output terminal 204, and the image projection unit 5 includes at least one projection lens 50 corresponding and adjacent to the image display panel 40. For example, the image display panel 40 may be a DLP (digital light processing) or a liquid crystal on silicon (LCOS) panel.
Therefore, the first predetermined light source L1, the second predetermined light source L2 and the third predetermined light source L3 can concurrently pass through the photonic crystal fiber structure 20 to form a mixed surface light source S (such as a rectangular surface light source, and the ratio of length to width is 16:9, 16:10 or 4:3) that can be projected onto the image display panel 40 from the light output terminal 204. The surface light source S can be reflected by the image display panel 40 to form an image light source P1 that can be projected onto the projection lens 50, and the image light source P1 can pass through the projection lens 50 to form an image projection light source P2 that can be projected onto a screen.
For another example, referring to
More precisely, the first emission angle adjusting module 61 includes a first light-diverging lens 610 adjacent to the first light-emitting module 11 and a first light-condensing lens 611 disposed between the first light-diverging lens 610 and the first light input terminal 201 of the photonic crystal fiber structure 20. The second emission angle adjusting module 62 includes a second light-diverging lens 620 adjacent to the second light-emitting module 12 and a second light-condensing lens 621 disposed between the second light-diverging lens 620 and the second light input terminal 202 of the photonic crystal fiber structure 20, and the third emission angle adjusting module 63 includes a third light-diverging lens 630 adjacent to the third light-emitting module 13 and a third light-condensing lens 631 disposed between the third light-diverging lens 630 and the third light input terminal 203 of the photonic crystal fiber structure 20. However, the light-condensing unit 6 used in the first embodiment is merely an example and is not meant to limit the instant disclosure.
Hence, the first predetermined light source L1, the second predetermined light source L2 and the third predetermined light source L3 can respectively pass through the first emission angle adjusting module 61, the second emission angle adjusting module 62 and the third emission angle adjusting module 63, thus the incident half angle θ2 of the incident light projected onto the photonic crystal fiber structure 20 can be adjusted to equal to or smaller than 15 degrees (θ2≦15°), thus the light-receiving efficiency of the photonic crystal fiber structure 20 for receiving the incident light can be increased.
Referring to
Therefore, the first predetermined light source L1, the second predetermined light source L2 and the third predetermined light source L3 can concurrently pass through the photonic crystal fiber structure 20 to form a mixed surface light source S (such as a rectangular surface light source, and the ratio of length to width is 16:9, 16:10 or 4:3) that can be projected onto the polarization beam splitting prism 30 from the light output terminal 204. The surface light source S can be reflected substantially about 90 degrees by the polarization beam splitting prism 30 to form a reflecting light source R that can be projected onto the image display panel 40, the reflecting light source R can be reflected substantially about 180 degrees by the image display panel 40 to form an image light source P1 that can be projected onto the polarization beam splitting prism 30, and the image light source P1 can be sequentially pass through the polarization beam splitting prism 30 and the projection lens 50 to form an image projection light source P2 projected onto a screen.
In conclusion, because the light-guiding unit 2 includes at least one photonic crystal fiber structure 20 disposed between the light-emitting unit 1 and the image display unit 4 or between the light-emitting unit 1 and the prism unit 3, the light-transmitting efficiency of the projection device Z of the instant disclosure can be increased (i.e., the optical loss of the projection device Z of the instant disclosure can be decreased). In addition, the size of the projection device Z of the instant disclosure can be reduced due to the flexibility of the photonic crystal fiber structure.
The above-mentioned descriptions merely represent the preferred embodiments of the instant disclosure, without any intention or ability to limit the scope of the instant disclosure which is fully described only within the following claims. Various equivalent changes, alterations or modifications based on the claims of instant disclosure are all, consequently, viewed as being embraced by the scope of the instant disclosure.
Number | Date | Country | Kind |
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101222255 | Nov 2012 | TW | national |