Patent Application
20140292831
The present invention relates generally to a projection device and head-up display device, and particularly relates to a projection device and head-up display (“HUD”) device equipped with a neutral density filter.
Conventionally, a projection device equipped with a neutral density filter is known (for example, see Patent Reference 1).
Patent Reference 1 discloses a projection device equipped with a light source lamp that generates illumination light, and a neutral density filter that includes a gradation section that continuously changes transmittance of the illumination light irradiated from the light source lamp.
In the projection device described in the above Patent Reference 1, because the neutral density filter is configured to continuously change transmittance of the illumination light irradiated from the light source lamp by the gradation section, the neutral density filter has a disadvantage where the size of the neutral density filter becomes large, inasmuch as the gradation section includes sections having various sizes of transmittance. Thus, suppressing the projection device from increasing in size is difficult.
One or more embodiments of the present invention are directed to a projection device and head-up display device that can suppress an increase in size.
A projection device according to one or more embodiments may comprise a laser light generator that outputs a laser light based on input image signals; a projector that comprises a scanner that scans the laser light irradiated from the laser light generator and projects an image on a projection area; a neutral density filter that coarsely adjusts brightness of the projected image by incrementally changing transmittance of the laser light irradiated from the laser light generator; and a laser output controller that finely adjusts brightness of the projected image by changing light intensity of the laser light by performing output adjustment of the laser light irradiated from the laser light generator.
As a result, in one or more embodiments, by providing the neutral density filter that coarsely adjusts brightness of the projected image by incrementally changing transmittance of the laser light irradiated from the laser light generator, the neutral density filter can be decreased in size in proportion to the decrease in the number of sections having a different transmittance compared to when gradation sections continuously change transmittance is included. By this, the projection device can be suppressed from increasing in size. Moreover, the brightness of the image can be changed smoothly because the brightness of the image coarsely adjusted by the neutral density filter can be finely adjusted by the laser controller, which finely adjusts the brightness of the projected image by changing the light intensity of the laser light by performing output adjustment of the laser light irradiated from the laser light generator.
According to one or more embodiments, for example, the neutral density filter may be configured to change the transmittance of the laser light by a predetermined number of increments.
According to one or more embodiments, for example, the laser output controller may be configured to change the light intensity of the laser light in a predetermined range, for example in a range of 1 to 1/α.
As another example, in one or more embodiments, the laser output controller may be configured to finely adjust the light intensity of the laser light down to 1/α, and the neutral density filter may be configured to incrementally change transmittance 1/α times at a time. The brightness of the image may be configured to be finely adjusted by the laser controller while the neutral density filter unit coarsely adjusts the brightness of the image incrementally. By being configured in this manner, the brightness of the image can be adjusted while being smoothly changed in a wide range by combining the fine adjustment of the laser controller and the coarse adjustment of the neutral density filter that changes transmittance 1/α times at a time.
As another example, in one or more embodiments, the neutral density filter may comprise a first neutral density filter; and a second neutral density filter disposed in an optical path direction of the laser light relative to the first neutral density filter, wherein transmittance is configured to change incrementally by combining the first neutral density filter and the second neutral density filter.
In one or more embodiments, when the neutral density filter includes a first neutral density filter and a second neutral density filter, the first neutral density filter may have incremental transmittance and may include a plurality of filters arranged in a direction that intersects the optical path direction of the laser light, the second neutral density filter may have incremental transmittance and may include a plurality of filters arranged in the direction that intersects the optical path direction of the laser light, and the neutral density filter may further include a driver that moves the first neutral density filter and the second neutral density filter in the direction that intersects the optical path direction of the laser light to change a combination of the plurality of filters of the first neutral density filter and the plurality of filters of the second neutral density filter. By being configured in this manner, the direction that intersects the optical path direction of the laser light of the neutral density filter can be made smaller in size because transmittances at various increments can be realized by superimposing the plurality of neutral density filters, compared to when realizing all transmittances by one neutral density filter. Moreover, transmittance of the neutral density filter can be changed easily because a driver can change the combination of the plurality of filters of the first neutral density filter and the plurality of filters of the second neutral density filter.
In one or more embodiments, the first neutral density filter may include a plurality of types of filters with transmittance expressed by an integer power of 1/α, the second neutral density filter may include a plurality of types of filters with transmittance expressed by an integer power of 1/α, and the neutral density filter is configured to change transmittance incrementally 1/α times at a time in (N+1) increments from 1 to the Nth power of 1/α, by combining the plurality of filters of the first neutral density filter and the plurality of filters of the second neutral density filter. By being configured in this manner, transmittance can be changed easily and incrementally in (N+1) increments from 1 to the Nth power of 1/α, 1/α times at a time by combining the plurality of types of filters of the first neutral density filter and the plurality of types of filters of the second neutral density filter.
In one or more embodiments, the neutral density filter may be configured to change transmittance incrementally in increments of between five and seven from 1 to 1/1000 or less by combining one of the plurality of filters of the first neutral density filter and one of the plurality of filters of the second neutral density filter. By being configured in this manner, the brightness of the image can be adjusted smoothly in a wide range easily by combining the fine adjustment of the laser controller because the brightness of the image can be coarsely adjusted incrementally in five or more increments and seven or fewer increments from a range of 1 to 1/1000 or less.
A head-up display device, according to one or more embodiments, may be equipped with a laser light generator that outputs the laser light based on input image signals, a projector that comprises the scanner that scans the laser light irradiated from the laser light generator and projects an image on a display panel disposed in a view direction of a user, a neutral density filter that coarsely adjusts brightness of the projected image by incrementally changing transmittance of the laser light irradiated from the laser light generator, and a laser output controller that finely adjusts brightness of the projected image by changing light intensity of the laser light by performing output adjustment of the laser light irradiated from the laser light generator.
A projection device size control method, according to one or more embodiments, may comprise outputting laser light based on input image signals; scanning the laser light and projecting an image on a projection area; coarsely adjusting brightness of the projected image by incrementally changing transmittance of the laser light; and finely adjusting brightness of the projected image by changing light intensity of the laser light by performing output adjustment of the laser light.
As another example, in one or more embodiments, by providing the neutral density filter that coarsely adjusts brightness of the projected image by incrementally changing transmittance of the laser light irradiated from the laser light generator, the neutral density filter can be decreased in size in proportion to the decrease in the number of sections having a different transmittance compared to when gradation sections continuously change transmittance is included. By this, the head-up display device can be suppressed from increasing in size. Such an effect is particularly effective in a head-up display device for which a decrease in size is desirable. Moreover, the brightness of the image can be changed smoothly because the brightness of the image coarsely adjusted by the neutral density filter can be finely adjusted by the laser controller by providing the laser controller that finely adjusts the brightness of the projected image by changing the light intensity of the laser light by performing output adjustment of the laser light irradiated from the laser light generator.
One or more embodiments, as described above, can suppress the projection device and head-up display device from increasing in size.
One or more embodiments of the present invention are described below with reference to the drawings.
One or more embodiments of a head-up display device 1 according to a first example will be described with reference to
The head-up display device 1 according to one or more embodiments, as illustrated in
Furthermore, the head-up display device 1, as illustrated in
Furthermore, according to one or more embodiments of the first example, the head-up display device 1 is equipped with a neutral density filter 20, a projector 21, an ambient light sensor 22, and an optical lens 23. The neutral density filter 20 includes a first neutral density filter 20a and a second neutral density filter 20b disposed in an optical path direction of a laser light relative to the first neutral density filter 20a. Moreover, as illustrated in
The video processor 11 is configured to control projection of video based on video signals input from external equipment such as a car navigation device. The video processor 11 is configured to control irradiation of the laser light by the red LD 18a, the green LD 18b, and the blue LD 18c via the laser controller 12 based on video signals input from outside, and to control driving of the MEMS mirror 21a via the mirror controller 16.
Furthermore, the video processor 11 is configured to adjust a brightness of a projected image based on an external brightness detected by the ambient light sensor 22. The video processor 11 is configured to perform output adjustment of the laser light irradiated from the red LD 18a, the green LD 18b, and the blue LD 18c via the laser controller 12, and to adjust transmittance of the laser light of the neutral density filter 20 via the drive controller 14.
The head-up display device 1, as illustrated in
The laser controller 12 is configured to control irradiation of the laser light by the red LD 18a, the green LD 18b, and the blue LD 18c by controlling the LD driver 13 based on controls by the video processor 11. The laser controller 12 is configured to control a laser light of a color corresponding to each pixel of the image to irradiate from the red LD 18a, the green LD 18b, and the blue LD 18c, to match the scanning timing of the MEMS mirror 21a.
Furthermore, the laser controller 12 is configured to adjust output of the laser light irradiated from the red LD 18a, the green LD 18b, and the blue LD 18c by controlling the LD driver 13. The laser controller 12 is configured to adjust output of the laser light in a range of 1 to 1/α (for example, α is about 4.14). In other words, the laser controller 12 is configured to finely adjust the brightness of the projected image by finely adjusting the light intensity of the laser light down to 1/α times.
The drive controller 14 is configured to change transmittance of the laser light of the neutral density filter 20 by controlling the stepping motor 15 based on controls by the video processor 11. The drive controller 14 is configured to move respectively, by the stepping motor 15, the first neutral density filter 20a and the second neutral density filter 20b of the neutral density filter 20 in the direction that intersects the optical path direction of the laser light. By this, as illustrated in
The mirror controller 16 is configured to control driving of the MEMS mirror 21a by controlling the mirror driver 17 based on controls by the video processor 11.
The red LD 18a is configured to irradiate a red laser light to the MEMS mirror 21a by passing through the polarized beam splitter 19b, the optical lens 23, and the neutral density filter 20. The green LD 18b is configured to irradiate a green laser light to the MEMS mirror 21a by passing through the polarized beam splitters 19a and 19b, the optical lens 23, and the neutral density filter 20. The blue LD 18c is configured to irradiate a blue laser light to the MEMS mirror 21a by passing through the polarized beam splitters 19a and 19b, the optical lens 23, and the neutral density filter 20.
Here, in one or more embodiments of the first example, the neutral density filter 20 is configured to coarsely adjust brightness of the projected image by incrementally changing transmittance of the laser light irradiated from the red LD 18a, the green LD 18b, and the blue LD 18c. The neutral density filter 20 is configured to incrementally change transmittance 1/α times at a time. In detail, as illustrated in
Furthermore, the laser controller 12 finely adjusts the brightness of the image while the neutral density filter 20 coarsely adjusts the brightness of the image incrementally. In other words, the dimming ratio is adjusted in a range of 1 to 1/5000 by making transmittance of the neutral density filter 20 any of states 1/α0, 1/α1, 1/α2, 1/α3, 1/α4, or 1/α5 and finely adjusting luminance (output) of each LD by the laser controller 12 in a range from 1 to 1/α.
Here, a value of α can be determined by a minimum value Rm of the dimming ratio and a coarsely adjusted incremental number S. Rm is (1/α) to the power of S. For example, when the minimum value Rm of the dimming ratio is 1/5000 and the coarsely adjusted incremental number S is 6, α is about 4.14. Further, a may be set from a range in which laser light output can be stably controlled. In this case, the coarsely adjusted incremental number S can be chosen from the minimum value Rm of the dimming ratio and α.
Furthermore, in one or more embodiments of the first example, as illustrated in
Furthermore, a transmittance of the filter 203a having the smallest transmittance among the filters of the first neutral density filter 20a and a transmittance of the filter 203b having the smallest transmittance among the filters of the second neutral density filter 20b may be either the same or one is 1/α times the other.
Furthermore, the neutral density filter 20 is configured to change transmittance incrementally by combining the filters 201a to 203a of the first neutral density filter 20a and the filters 201b to 203b of the second neutral density filter 20b. The neutral density filter 20 is configured to change transmittance incrementally in six increments from 1 to the fifth power of 1/α 1/α times at a time by combining the plurality of filters 201a to 203a and the plurality of filters 201b to 203b.
For example, as illustrated in
For coarse adjustment step 2 (1/α2 transmittance), the filter 201a (1/α0 transmittance) of the first neutral density filter 20a and the filter 202b (1/α2 transmittance) of the second neutral density filter 20b are combined. In other words, when migrating from coarse adjustment step 1 to coarse adjustment step 2, the first neutral density filter 20a is moved the width of one filter in an X2 direction by the stepping motor 15, and the second neutral density filter 20b is moved the width of one filter in the X2 direction by the stepping motor 15.
For coarse adjustment step 3 (1/α3 transmittance), the filter 201a (1/α0 transmittance) of the first neutral density filter 20a and the filter 203b (1/α3 transmittance) of the second neutral density filter 20b are combined. In other words, when migrating from coarse adjustment step 2 to coarse adjustment step 3, the second neutral density filter 20b is moved the width of one filter in the X2 direction by the stepping motor 15.
For coarse adjustment step 4 (1/α4 transmittance), the filter 202a (1/α1 transmittance) of the first neutral density filter 20a and the filter 203b (1/α3 transmittance) of the second neutral density filter 20b are combined. In other words, when migrating from coarse adjustment step 3 to coarse adjustment step 4, the first neutral density filter 20a is moved the width of one filter in the X1 direction by the stepping motor 15.
For coarse adjustment step 5 (1/α5 transmittance), the filter 203a (1/α2 transmittance) of the first neutral density filter 20a and the filter 203b (1/α3 transmittance) of the second neutral density filter 20b are combined. In other words, when migrating from coarse adjustment step 4 to coarse adjustment step 5, the first neutral density filter 20a is moved the width of one filter in the X1 direction by the stepping motor 15.
In coarse adjustment steps 2 to 4, a combination of the first neutral density filter 20a and the second neutral density filter 20b may be another combination. For example, for coarse adjustment step 3 (1/α3 transmittance), the filter 202a (1/α1 transmittance) of the first neutral density filter 20a and the second neutral density filter 202b (1/α2 transmittance) of the filter 20b may be combined.
As described above, the dimming ratio is coarsely adjusted by the neutral density filter 20 while migrating coarse adjustment steps. Moreover, the brightness of the image can be changed continuously (without suddenly brightening or darkening) because a coarse adjustment step can be migrated to an adjacent coarse adjustment step by moving the first neutral density filter 20a and the second neutral density filter 20b within the width of one filter.
The video projector 21 is configured to project images on the windshield 2. The MEMS mirror 21a of the video projector 21 is configured to scan a laser light irradiated from the red LD 18a, the green LD 18b, and the blue LD 18c and project images on the windshield 2. The MEMS mirror 21a is configured to operate on two axes, in a horizontal direction and in a vertical direction, and scan a laser light. Moreover, the MEMS mirror 21a is configured to scan the horizontal direction at a high speed by a resonant drive and to scan the vertical direction at a low speed by a direct current drive.
In one or more embodiments of the first example, the neutral density filter 20 can be decreased in size inasmuch as a number of sections having a different transmittance compared to when gradation sections to continuously change transmittance is included is decreased, by providing the neutral density filter 20 that coarsely adjusts brightness of the projected image by incrementally changing transmittance of the laser light irradiated from the red LD 18a, the green LD 18b, and the blue LD 18c. By this, the head-up display device 1 can be suppressed from increasing in size. Moreover, the brightness of the image can be changed smoothly because the brightness of the image coarsely adjusted by the neutral density filter 20 can be finely adjusted by the laser controller 12 by providing the laser controller 12 that finely adjusts the brightness of the projected image by changing the light intensity of the laser light by performing output adjustment of the laser light irradiated from the red LD 18a, the green LD 18b, and the blue LD 18c.
Furthermore, in one or more embodiments of the first example, the laser controller 12 is configured to finely adjust the light intensity of the laser light down to 1/α times, and the neutral density filter 20 is configured to incrementally change transmittance 1/α times at a time. Moreover, the brightness of the image is configured to be finely adjusted by the laser controller 12 while the neutral density filter 20 coarsely adjusts the brightness of the image incrementally. By this, the brightness of the image can be adjusted while being smoothly changed in a wide range by combining the fine adjustment of the laser controller 12 and the coarse adjustment of the neutral density filter 20 that changes transmittance 1/α times at a time.
Furthermore, in one or more embodiments of the first example, transmittance is configured to change incrementally by combining the filters 201a to 203a of the first neutral density filter 20a and the filters 201b to 203b of the second neutral density filter 20b. By this, the neutral density filter 20 can easily be made to a desired transmittance by combining the filters 201a to 203a of the first neutral density filter 20a and the filters 201b to 203b of the second neutral density filter 20b.
Furthermore, in one or more embodiments of the first example, the plurality of filters 201a to 203a having incremental transmittance and arranged in the direction that intersects the optical path direction of the laser light and the plurality of filters 201b to 203b having incremental transmittance and arranged in the direction that intersects the optical path direction of the laser light are provided. Furthermore, the stepping motor 15 that moves the first neutral density filter 20a and the second neutral density filter 20b in the direction that intersects the optical path direction of the laser light to change the combination of the plurality of filters 201a to 203a and the plurality of filters 201b to 203b is provided. By this, the direction that intersects the optical path direction of the laser light of the neutral density filter 20 can be made smaller in size because transmittances at various increments can be realized by superimposing the plurality of neutral density filters, compared to when realizing all transmittances by one neutral density filter. Moreover, transmittance of the neutral density filter 20 can be changed easily because the stepping motor 15 can change the combination of the plurality of filters 201a to 203a and the plurality of filters 201b to 203b.
Furthermore, in one or more embodiments of the first example, a plurality of types of filters 201a to 203a with a transmittance expressed by an integer power of 1/α and a plurality of types of filters 201b to 203b with a transmittance expressed by an integer power of 1/α are provided. Moreover, the neutral density filter 20 is configured to change transmittance incrementally in six increments from 1 to the fifth power of 1/α 1/α times at a time by combining the plurality of filters 201a to 203a and the plurality of filters 201b to 201c. By this, transmittance can be changed easily and incrementally in six increments from 1 to the fifth power of 1/α 1/α times at a time by combining the plurality of types of filters 201a to 203a and the plurality of types of filters 201b to 203b.
Furthermore, in one or more embodiments of the first example, the neutral density filter 20 is configured to change transmittance incrementally in six increments from 1 to 1/1200 by combining the filters 201a to 203a of the first neutral density filter 20a and the filters 201b to 203b of the second neutral density filter 20b. By this, the brightness of the image can be adjusted smoothly in a wide range easily by combining the fine adjustment of the laser controller 12 because the brightness of the image can be coarsely adjusted incrementally in six increments in a range from 1 to about 1/1200.
A first modification of the previously described one or more embodiments of the first example is described below. As illustrated in
In the first modification of the previously described one or more embodiments of the first example, a neutral density filter 30 is configured to coarsely adjust transmittance (dimming ratio) in six increments of 1/α0 (=1), 1/α1, 1/α2, 1/α3, 1/α4, and 1/α5. Furthermore, as illustrated in
Other configurations of the first modification of the previously described one or more embodiments of the first example may be the same as the previously described one or more embodiments of the first example.
A second modification of the previously described one or more embodiments of the first example is described below. As illustrated in
In the second modification of the previously described one or more embodiments of the first example, a neutral density filter 40 is configured to coarsely adjust transmittance (dimming ratio) in six increments of 1/α0 (=1), 1/α1, 1/α2, 1/α3, 1/α4, and 1/α5. Furthermore, as illustrated in
Other configurations of the second modification of the previously described one or more embodiments of the first example may be the same as the previously described one or more embodiments of the first example.
Next, one or more embodiments of a second example of the present invention will be described with reference to
Here, in one or more embodiments of a second example, a neutral density filter 50 is configured to coarsely adjust transmittance (dimming ratio) in five increments of 1/α0 (=1), 1/α1, 1/α2, 1/α3, and 1/α4. Furthermore, as illustrated in
Other configurations of one or more embodiments of a second example may be the same as the previously described one or more embodiments of the first example.
As described above, in one or more embodiments of a second example, the head-up display device 1 can also be suppressed from increasing size by providing the neutral density filter 50 that coarsely adjusts brightness of the projected image by incrementally changing transmittance of a laser light irradiated from a red LD 18a, a green LD 18b, and a green LD 18c.
Other effects of one or more embodiments of the second example may be the same as the previously described one or more embodiments of the first example.
A first modification of one or more embodiments of the second example is described below. As illustrated in
In the first modification of one or more embodiments of the second example, a neutral density filter 60 is configured to coarsely adjust transmittance (dimming ratio) in five increments of 1/α0 (=1), 1/α1, 1/α2, 1/α3, and 1/α4. Furthermore, as illustrated in
Other configurations of the first modification of one or more embodiments of the second example may be the same as the previously described one or more embodiments of the second example.
Next, one or more embodiments of a third example of the present invention will be described with reference to
Here, in one or more embodiments of a third example, a neutral density filter 70 is configured to coarsely adjust transmittance (dimming ratio) in seven increments of 1/α0 (=1), 1/α1, 1/α2, 1/α3, 1/α4, 1/α5, and 1/α6. Furthermore, as illustrated in
Other configurations of one or more embodiments of a third example may be the same as the previously described one or more embodiments of the first example.
As described above, in one or more embodiments of a third example, the head-up display device 1 can also be suppressed from increasing size by providing the neutral density filter 70 that coarsely adjusts brightness of the projected image by incrementally changing transmittance of a laser light irradiated from a red LD 18a, a green LD 18b, and a green LD 18c.
Other effects of one or more embodiments of a third example may be the same as the previously described one or more embodiments of the first example.
A first modification of one or more embodiments of the third example is described below. As illustrated in
In the first modification of one or more embodiments of the third example, a neutral density filter 80 is configured to coarsely adjust transmittance (dimming ratio) in seven increments of 1/α0 (=1), 1/α1, 1/α2, 1/α3, 1/α4, 1/α5, and 1/α6. Furthermore, as illustrated in
Other configurations of the first modification of one or more embodiments of the third example may be the same as the previously described one or more embodiments of the third example.
The embodiments herein disclosed are examples on all points and should be considered as not restrictive. The scope of the present invention is indicated by the scope of the claims and not by the descriptions of the embodiments described above and furthermore includes all equivalent meanings of the scope of the claims and all modifications within the scope of the claims.
For example, in one or more embodiments described above, an example is given in which the present invention is applied to a head-up display device, but the present invention is not limited to this. In the present invention, the present invention may be applied to a projection device other than a head-up display device.
Furthermore, in one or more embodiments described above, an example is given in which an image is projected on a windshield of a car as a projection area, but the present invention is not limited to this. In the present invention, the image may be projected on a projection area such as a screen.
Furthermore, in one or more embodiments described above, an example is given in which two neutral density filters, a first neutral density filter and a second neutral density filter, were combined to change transmittance of a laser light, but the present invention is not limited to this. In the present invention, one neutral density filter may change transmittance of the laser light, or three or more neutral density filters may be combined to change transmittance of the laser light.
Furthermore, in one or more embodiments described above, examples are given of configurations in which the neutral density filter coarsely adjusts transmittance (dimming ratio) in six increments, five increments, and seven increments, but the present invention is not limited to this. In the present invention, the neutral density filter may coarsely adjust transmittance in four increments or less or in eight increments or more.
Furthermore, in one or more embodiments of a first example described above, an example is given of a configuration in which transmittance is changed from 1 to about 1/1200 by combining the plurality of filters of the first neutral density filter and the plurality of filters of the second neutral density filter, but the present invention is not limited to this. In the present invention, a configuration that changes transmittance from 1 to about 1/1200 is not necessary if a configuration that changes transmittance from 1 to 1/1000 or less by combining the plurality of filters of the first neutral density filter and the plurality of filters of the second neutral density filter is provided.
Furthermore, in one or more embodiments described above, an example is given of a configuration in which brightness of the projected image is adjusted in a range of dimming ratio 1 to 1/5000, but the present invention is not limited to this. In the present invention, brightness of the projected image may be adjusted in a range other than dimming ratio 1 to 1/5000.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2013-071120 | Mar 2013 | JP | national |
