WO2016121534A1

WO2016121534A1 - Display device

Info

Publication number: WO2016121534A1
Application number: PCT/JP2016/051142
Authority: WO
Inventors: 川井　清幸; 大西　道久
Original assignee: アルプス電気株式会社
Priority date: 2015-01-29
Filing date: 2016-01-15
Publication date: 2016-08-04

Abstract

Provided is a display device capable of irradiating and focusing a beam onto each screen whereon an intermediate image is formed by beam scanning. The display device comprises: a scanner 30 for selectively reflecting a beam from a light source 20 toward either one of two screens (51, 52) and scanning the screens (51, 52) with the reflected beam; a projection optical system 60 for projecting an image according to the intermediate image formed on the screens (51, 52) by the beam scanning with the scanner 30; and intermediate optical systems (41, 42) respectively disposed in a light path from the scanner 30 to one screen 51 and in another light path from the scanner 30 to the other screen 52, and focusing the beam from the scanner 30 on the respective screens (51, 52).

Description

Display device

The present invention relates to a display device such as a head-up display device that forms a virtual image in front of a windshield of a vehicle using a light beam such as a laser beam.

Patent Document 1 includes a light source, a scanning unit that scans a light beam from the light source, a diffuser that forms an intermediate image by scanning the light beam of the scanning unit, and a projection unit that projects the intermediate image formed on the diffuser. A vehicle head-up display device that projects a virtual image in front of a driver by reflecting light of an intermediate image emitted from a screen by a projection unit is disclosed. In the example shown in FIGS. 1 and 2, the virtual image display distance can be changed by changing the position of the diffuser. In the example shown in FIG. 3, the plurality of diffusers are arranged so that the distance and the position from the scanning unit are different, and thereby the virtual image display distance can be changed.

JP 2009-150947 A

Here, the scan image projected on the diffuser has a higher resolution as the beam diameter of the projection light is smaller. However, in the vehicle head-up display device shown in Patent Document 1, the diffuser provided at a plurality of different positions is used. On the other hand, since the scan image is projected as it is, when the parallelism of the light incident on the scanning means is low, if the beam diameter of the light projected on one of the plurality of diffusers at different positions is minimized, The beam diameter of the light beam projected on the diffuser other than the above becomes large. On the other hand, when the parallelism of the light rays incident on the scanning means is increased, the change in the beam diameter accompanying the change in the position of the diffuser is reduced, but it is difficult to narrow down the beam diameter.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a display device capable of injecting light beams while focusing on each screen on which an intermediate image is formed by scanning the light beams. It is in.

A display device according to the present invention is a display device that displays an image corresponding to an intermediate image formed on each of two screens. The light source emits a light beam, and the light beam from the light source is transmitted between the two screens. A scanner that selectively reflects toward either one and scans the screen with the reflected light beam, and a projection that projects an image corresponding to the intermediate image formed on the screen by scanning the light beam of the scanner An optical system is disposed in at least one of an optical path from the scanner to one of the screens and an optical path from the scanner to the other of the screens, and the focal point of the light beam from the scanner in the screen on the arranged optical path. And at least one intermediate optical system. In each of the two screens, the rays from the scanner are in focus.

According to the above configuration, the intermediate optical system is disposed in at least one of an optical path from the scanner to the one screen and an optical path from the scanner to the other screen. In the screen on the optical path where the intermediate optical system is disposed, the light beam from the scanner is focused by the intermediate optical system. Further, when there is the screen on which the lens is not disposed on the optical path, the light beam from the scanner is focused on the screen without using the intermediate optical system. The system focuses the light beam from the scanner. Accordingly, it becomes possible to make the light beam enter the focused screen on each of the two screens on which the intermediate image is formed by scanning the light beam.

Preferably, the intermediate optical system having a positive refractive power may be disposed in an optical path from the scanner to one of the screens and an optical path from the scanner to the other of the screens.
In this case, the length of the optical path from the scanner to the one screen may be relatively different from the length of the optical path from the scanner to the other screen, and the optical path arranged in the relatively short optical path may be used. The intermediate optical system may have a larger positive refractive power than the intermediate optical system disposed in the relatively long optical path.

Preferably, the intermediate optical system having a negative refractive power may be disposed in an optical path from the scanner to one of the screens and an optical path from the scanner to the other screen.
In this case, the length of the optical path from the scanner to the one screen may be relatively different from the length of the optical path from the scanner to the other screen, and the optical path arranged in the relatively long optical path may be used. The intermediate optical system may have a larger negative refractive power than the intermediate optical system disposed in the relatively short optical path.

Preferably, the intermediate optical system having a positive refractive power is disposed in an optical path from the scanner to one of the screens, and the intermediate optical system having a negative refractive power is disposed in an optical path from the scanner to the other of the screens. May be arranged.
In this case, the optical path in which the intermediate optical system having the positive refractive power is arranged may be shorter than the optical path in which the intermediate optical system having the negative refractive power is arranged.
According to said structure, it becomes easy to focus on each of two screens which distanced.

Preferably, the intermediate optical system disposed in an optical path from the scanner to one of the screens and the intermediate optical system disposed in an optical path from the scanner to the other screen have a common optical axis. Good. In this case, the scanner may reflect the light beam from the light source on a reflection surface that can rotate around an axis passing through the common optical axis.
According to said structure, it becomes easy to make a light beam accurately inject into each of two said intermediate | middle optical systems from the said scanner, aiming at size reduction of an apparatus.

Preferably, the intermediate optical system may be arranged in any one of an optical path from the scanner to the one screen and an optical path from the scanner to the other screen.
In this case, the intermediate optical system may have a positive refractive power, and the optical path in which the intermediate optical system having the positive refractive power is disposed may be shorter than the optical path in which the intermediate optical system is not disposed. .
Alternatively, in this case, the intermediate optical system may have a negative refractive power, and the optical path in which the intermediate optical system having the negative refractive power is disposed is longer than the optical path in which the intermediate optical system is not disposed. It's okay.
According to the above configuration, the number of intermediate optical systems used is reduced.

Preferably, the scanner may reflect a light beam from the light source on a rotating reflecting surface. In this case, the distance from the reflecting surface to the intermediate optical system and the distance from the intermediate optical system to the screen may both be equal to the focal length of the intermediate optical system.
According to the above configuration, since the light beam from the scanner can be focused on the screen, the beam diameter of the light beam on the screen is reduced, and the resolution of the intermediate image is increased.

According to the present invention, since the light beam can be focused on each screen (for example, a diffuser) on which the intermediate image is formed by scanning the light beam, the resolution of the intermediate image can be increased.

It is a top view which shows an example of a structure of the display apparatus which concerns on 1st Embodiment. It is a block diagram which shows the structure of the display apparatus shown in FIG. FIG. 2 is a partially enlarged view of FIG. 1. It is a top view which shows the example which applied the display apparatus which concerns on 1st Embodiment to the head-up display apparatus for vehicles. It is a top view which shows an example of a structure of the display apparatus which concerns on 2nd Embodiment. It is a top view which shows an example of a structure of the display apparatus which concerns on 3rd Embodiment. It is a top view which shows an example of a structure of the display apparatus which concerns on 4th Embodiment. It is a top view which shows an example of a structure of the display apparatus which concerns on 5th Embodiment.

<First Embodiment>
Hereinafter, a display device according to a first embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a plan view showing a configuration of a display device 10 according to the present embodiment. FIG. 2 is a block diagram showing the configuration of the display device 10 shown in FIG. FIG. 3 is a partially enlarged view of FIG.
As shown in FIG. 1 or 2, the display device 10 includes a light source 20, a scanner 30 as a scanning unit, a first lens 41 as an intermediate optical system, a second lens 42 as an intermediate optical system, 1 screen 51, 2nd screen 52, the projection lens 60 as a projection optical system, the light source driver 21, the scanner driver 31, the control part 70, and the memory 71 are provided.

The light source 20 is a light source that emits amplitude-modulated visible region laser light as parallel light, and emits light having an intensity corresponding to the amount of current supplied from the light source driver 21. The amplitude modulation and the amount of current supplied from the light source driver 21 are controlled by the control unit 70.

The scanner 30 is, for example, a galvanometer mirror or a MEMS mirror, and the scanner driver 31 rotates the reflecting surface 33 around an axis passing through the rear shaft 60c of the projection lens 60. The laser light emitted from the light source 20 is selectively reflected toward one of the first screen 51 and the second screen 52 by the rotating reflecting surface 33 and emitted as scanning light to the two scanning regions. The The two scanning regions are a first scanning region A1 (FIG. 3) where the scanning light is incident on the first lens 41 and a second scanning region A2 (FIG. 3) where the scanning light is incident on the second lens 42. . Hereinafter, the traveling direction of reflected light from the scanner 30 toward the first scanning region A1 is defined as a first reflecting direction D1, and the traveling direction of reflected light from the scanner 30 toward the second scanning region A2 is defined as a second reflection. This will be described as the direction D2.

The rotation direction and rotation speed of the scanner 30 are controlled by the control unit 70, and the scanner driver 31 rotates the scanner 30 in accordance with a control signal from the control unit 70. The axis on which the reflecting surface 33 of the scanner 30 rotates is disposed on an extension line of the optical axis 60c of the projection lens 60, and extends, for example, in the Y-axis direction and the Z-axis direction (direction perpendicular to the paper surface of FIG. 3). Yes. In each figure, the XY plane is a plane perpendicular to the Z-axis direction.

On the first reflection direction D1 by the scanner 30, a first lens 41 and a first screen 51 are arranged in order from the scanner 30 side. That is, the first lens 41 is disposed on the optical path from the scanner 30 to the first screen 51.
Further, a second lens 42 and a second screen 52 are arranged in this order from the scanner 30 side on a second reflection direction D2 different from the first reflection direction D1. That is, the second lens 42 is disposed on the optical path from the scanner 30 to the second screen 52.

The first lens 41 and the second lens 42 are arranged at positions where light emitted from one side does not enter the other. In other words, the first scanning area A1 and the second scanning area A2 do not overlap each other.

The first lens 41 is a biconvex positive lens arranged so that its optical axis is on the extended line of the optical axis 60c of the projection lens 60, and the first reflected light reflected in the first reflection direction D1 ( First scanning light) is condensed to form a first intermediate image on the first screen 51. The first intermediate image is formed in a predetermined range of the first screen 51 by a scanning operation in which the incident light from the light source 20 is reflected by the reflecting surface 33 while rotating the scanner 30 around the rotation axis. Here, the optical axis of the first lens 41 connects the center of curvature of the first surface 41a (surface on the scanner 30 side) on the object side and the center of curvature of the second surface 41b (surface on the projection lens 60 side) on the image side. The first lens 41 uses a portion above the optical axis in the Y-axis direction of FIG. The first screen 51 is, for example, a diffuser (diffusion plate) that emits incident light as diffused light. On the optical axis 60c of the projection lens 60, the distance between the reflection point 33a on the reflection surface 33 and the first surface 41a (front surface) of the first lens 41, and the second surface 41b (rear surface) of the first lens 41 and the first surface. The distance from the incident surface 51a of one screen 51 is equal to the focal length f1 of the first lens 41, respectively. Here, the reflection point 33 a is disposed on an extension line of the optical axis 60 c of the projection lens 60.

The second lens 42 is a biconvex positive lens arranged so that its optical axis is on the extension line of the optical axis 60 c of the projection lens 60, and has a refractive index different from that of the first lens 41. The second lens 42 collects the second reflected light (second scanning light) reflected in the second reflection direction D <b> 2 and forms a second intermediate image on the second screen 52. The second intermediate image is formed in a predetermined range of the second screen 52 by a scanning operation in which incident light from the light source 20 is reflected by the reflecting surface 33 while rotating the scanner 30 around the rotation axis. Here, the optical axis of the second lens 42 is a line connecting the center of curvature of the first surface 42a on the object side and the center of curvature of the second surface 42b on the image side, and the second lens 42 has the Y axis in FIG. In the direction, the portion below the optical axis is used. The second screen 52 is, for example, a diffuser that emits incident light as diffused light. On the optical axis 60c of the projection lens 60, the distance between the reflection point 33a on the reflection surface 33 and the first surface 42a (front surface) of the second lens 42, and the second surface 42b (rear surface) of the second lens 42 and the first surface. The distance from the incident surface 52a of the two screens 52 is equal to the focal length f2 of the second lens 42, respectively.

The light rays incident on the first lens 41 and the second lens 42 are condensed to reduce the beam diameter, and become diffused light on the first screen 51 and the second screen 52, respectively, thereby suppressing speckle noise. Can do. Further, since the first lens 41 and the second lens 42 can focus on a spot having a small beam diameter, a high-definition intermediate image can be obtained. The first lens 41 and the second lens 42 may be lenses having different shapes as long as they have a positive refractive power. Moreover, it is good also as an optical system which consists of several lenses instead of a single lens.

The projection lens 60 is a biconvex positive lens, which enlarges the emitted light from the first screen 51 and the second screen 52, respectively, and makes virtual images I1 (first image) and I2 (first image) visible to the user's eye E. 2 images) are formed. The virtual image I1 based on the first intermediate image on the first screen 51 and the virtual image I2 based on the second intermediate image on the second screen 52 are different from each other with the optical axis 60c of the projection lens 60 in the Y-axis direction as a boundary. Formed in position. Further, the virtual image I1 and the virtual image I2 are formed at different positions also in the direction of the optical axis 60c of the projection lens 60 (X-axis direction).

In the display device 10, the virtual image display area is divided into two areas on the upper and lower sides of the optical axis 60c of the projection lens 60 in the Y-axis direction, that is, two areas corresponding to the two scanning areas A1 and A2. In order to form a virtual image in each of these areas, the first lens 41 and the first screen 51 are arranged in the upper scanning area A1, and the second lens 42 and the second screen 52 are arranged in the lower scanning area A2. It is arranged. Further, the light source 20, the scanner 30 as a scanning unit, and the projection lens 60 as a projection optical system were used as a common optical element. With such a configuration, different information can be displayed in the upper and lower regions in the Y-axis direction, and the images displayed in the two regions can have a difference in depth.

As shown in FIG. 1, the distance from the projection lens 60 to the eye E is D, the distance from the projection lens 60 to the first screen 51 is S1, the distance from the projection lens 60 to the virtual image I1 is S2, and the focus of the projection lens 60 When the distance is f3, the following formula (1) is established from the imaging formula.

1 / S1-1 / S2 = 1 / f3 (1)

Here, since the distance L between the eye E and the virtual image I1 is the sum of the distance D and the distance S2, it can be expressed by the following equation (2) from the above equation (1).

L = D + S2 = D + 1 / (1 / S1-1 / f3) (2)

Therefore, if the distance S1 from the projection lens 60 to the first screen 51 is changed, the distance L between the virtual image I1 and the eye E, that is, the display distance can be changed. For example, when the distance S1 between the projection lens 60 and the first screen 51 is reduced, the distance S2 between the projection lens 60 and the virtual image I1 is also reduced, so that the distance L between the driver's eye E and the virtual image I1 is also reduced.

This also applies to the virtual image I2, and the display distance of the virtual image I2 can be changed by changing the distance from the projection lens 60 to the second screen 52.

Since it is configured as described above, according to the basic mode, the following effects are obtained. This effect is the same for the example applied to the vehicle head-up display device described below.

(1) In the display device 10 according to the above-described embodiment, the first lens 41 having the positive refractive power and the first screen 51 are disposed in the first scanning region A1, and are different from the first scanning region A1. A second lens 42 having a positive refractive power and a second screen 52 are arranged in the second scanning region A2, respectively, and a projection optical system based on intermediate images formed on the first screen and the second screen, respectively. Thus, separate images are generated in different areas.
As a result, it is possible to make light beams focused (with a minimum beam diameter) incident on the first screen and the second screen arranged in different scanning regions, respectively. Therefore, it is possible to display the first image and the second image with high resolution in different areas.

(2) The distance from the reflecting surface 33 of the scanner 30 to the front surface of the corresponding first lens 41 and the distance from the rear surface of the first lens 41 to the corresponding first screen 51 are the focal points of the first lens 41. Each distance is equal. The distance from the reflecting surface 33 of the scanner 30 to the front surface of the corresponding second lens 42 and the distance from the rear surface of the second lens 42 to the corresponding second screen 52 are the focal length of the second lens 42. Are equal to each other.
As a result, the beam diameters of the light rays incident on the first screen 51 and the second screen 52 can be reduced, so that an image with high resolution can be generated.

(3) The optical axes of the second lens 42 corresponding to the first lens 41 are on the same straight line, and the rotation axis of the reflecting surface 33 of the corresponding scanner 30 is located on this straight line.
Thus, the reflected light from the scanner 30 to each of the first lens 41 and the second lens 42 can be accurately and easily separated, so that the image based on the light emitted from the first lens 41 and the second lens The image based on the emitted light from 42 can be displayed in a different area.

(4) The positive refractive power of the first lens 41 is larger than the positive refractive power of the corresponding second lens 42, and the first screen 51 is disposed closer to the reflecting surface 33 than the second screen 52. Yes.
Thereby, also in the direction of the optical axis 60c of the projection lens 60, two images can be displayed at different positions.

Next, an embodiment in which the display device according to this embodiment shown in FIGS. 1 to 3 is applied to a vehicle head-up display device will be described.

FIG. 4 is a plan view showing an example in which the display device according to the basic form is applied to a head-up display device 110 for a vehicle. In the head-up display device 110 shown in FIG. 4, the laser light source 120, the scanner 130, the first lens 141, the second lens 142, the first screen 151, the second screen 152, the first projection mirror 161, and The second projection mirror 162 includes the light source 20, the scanner 30, the first lens 41, the second lens 42, the first screen 51, the second screen 52, and the display device shown in FIGS. Each corresponds to the projection lens 60. In the head-up display device 110, the generated image light is reflected and enlarged by the first projection mirror 161 and the second projection mirror 162, and projected onto the display area of the windshield of the vehicle. This image light is reflected toward the driver in the display area, and at the same time, a virtual image is formed in front of the windshield.

The head-up display device 110 includes a case (not shown), and in this case, as shown in FIG. 4, a laser light source 120, a scanner 130 (scanning means), and a first lens 141 (on the optical base 111). An intermediate optical system), a second lens 142 (intermediate optical system), a first screen 151, a second screen 152, a first projection mirror 161, and a second projection mirror 162 (projection optical system). Yes.

The laser light source 120 is fixed to the optical base 111 and emits laser light in the visible region that is amplitude-modulated as parallel light.

The scanner 130 rotates around a rotation shaft 132 fixed to the optical base 111, and reflects incident light from the laser light source 120 to two scanning regions according to the direction of the reflecting surface 133. Similar to the display device shown in FIG. 1, the two scanning regions are a first scanning region where scanning light enters the first lens 141 and a second scanning region where scanning light enters the second lens 142. In the following description, the traveling direction of the reflected light from the scanner 130 toward the first scanning region is defined as a first reflecting direction D11, and the traveling direction of the reflected light from the scanner 130 toward the second scanning region is defined as a second traveling direction. The reflection direction is D12. The operation of the scanner 130 is controlled in the same manner as the scanner 30 in FIGS.

On the first reflection direction D11 by the scanner 130, a first lens 141 and a first screen 151 are arranged in this order from the scanner 130 side. A second lens 142 and a second screen 152 are arranged in this order from the scanner 130 side on a second reflection direction D12 different from the first reflection direction D11. The first lens 141 and the second lens 142 are disposed at a position where light emitted from one side does not enter the other. Therefore, the first scanning region and the second scanning region do not overlap each other.

The first lens 141 is configured and arranged in the same manner as the first lens 41 described above, and condenses the first reflected light reflected in the first reflection direction D1. The condensed light is sequentially reflected by the two light transmission mirrors 143 and 144 and then formed on the first screen 151 as a first intermediate image. Here, similarly to the first lens 41 described above, the distance between the reflection point on the reflection surface 133 and the surface of the first lens 141 on the scanner 130 side, and the surface of the first lens 141 on the first screen 151 side and the first surface. The distance from the incident surface of one screen 151 is equal to the focal length of the first lens 141.

The second lens 142 is configured and arranged in the same manner as the second lens 42 described above, and condenses the second reflected light reflected in the second reflection direction D12. The condensed light is sequentially reflected by the two light transmission mirrors 143 and 144 and then formed on the second screen 152 as a second intermediate image. Here, similarly to the second lens 42 described above, the distance between the reflection point on the reflection surface 133 and the surface of the second lens 142 on the scanner 130 side, and the surface of the second lens 142 on the second screen 152 side and the second lens 142. The distance from the incident surface of the two screens 152 is equal to the focal length of the second lens 142.

The first lens 141 and the second lens 142 are disposed outside the path of the reflected light from the first projection mirror 161. The first screen 151 and the second screen 152 are, for example, diffusers (diffusion plates).

The light that has passed through the

screens

151 and 152 becomes divergent projection light P1 and P2, respectively, and enters the first projection mirror 161 through the aperture 153a of the light shielding wall 153. The reflecting surface 161a of the first projection mirror 161 is a concave mirror (magnifying mirror), and the projection lights P1 and P2 including the intermediate images formed on the

screens

151 and 152 are magnified and reflected by the first projection mirror 161, respectively. . These reflected lights are incident on the second projection mirror 162, respectively. The reflecting surface 162a of the second projection mirror 162 is also a concave mirror (magnifying mirror), and the incident projection lights P1 and P2 are further magnified and reflected and projected onto different positions in the display area of the windshield of the vehicle. Since this display area functions as a semi-reflective surface, the incident image light is reflected toward the driver and a virtual image is formed in front of the windshield. By viewing the virtual image in front of the windshield, it appears to the driver that various types of information are displayed in front of the steering wheel.

<Second Embodiment>
FIG. 5 is a diagram showing an example of the configuration of a display device according to the second embodiment of the present invention.
The display device shown in FIG. 5 is obtained by replacing the first lens 41 and the second lens 42 as the intermediate optical system in the display device shown in FIG. 1 with a first lens 43 and a second lens 44, respectively.

The first lens 43 is a concave lens arranged so that its optical axis is on the extension line of the optical axis 60c of the projection lens 60, and has negative refractive power. The first lens 43 forms a first intermediate image on the first screen 51 by dispersing the first reflected light (first scanning light) reflected in the first reflection direction D1. The first lens 43 uses a portion above the optical axis in the Y-axis direction of FIG. On the optical axis 60 c of the projection lens 60, the distance between the reflection point on the reflection surface 33 and the surface of the first lens 43 on the scanner 30 side, and the surface of the first lens 43 on the first screen 51 side and the first screen 51. The distance from the incident surface is equal to the focal length of the first lens 43. Here, the reflection point of the reflection surface 33 is disposed on an extension line of the optical axis 60 c of the projection lens 60.

The second lens 44 is a concave lens arranged so that its optical axis is on the extension line of the optical axis 60 c of the projection lens 60, and has a negative refractive power larger than that of the first lens 43. The second lens 44 disperses the second reflected light (second scanning light) reflected in the second reflection direction D <b> 2 and forms a second intermediate image on the second screen 52. The second lens 44 uses a portion below the optical axis in the Y-axis direction of FIG. On the optical axis 60 c of the projection lens 60, the distance between the reflection point on the reflection surface 33 and the surface of the second lens 44 on the scanner 30 side, and the surface of the second lens 44 on the second screen 52 side and the second screen 52. The distance from the incident surface is equal to the focal length of the second lens 44.

In the display device shown in FIG. 5, since the distance from the reflecting surface 33 to the second screen 52 is longer than the distance from the reflecting surface 33 to the first screen 51, the second light beam is focused on these screens. The lens 44 has a larger negative refractive power than the first lens 43.

The display device according to the present embodiment can obtain the same effects as those of the display device according to the first embodiment, and can be applied to a head-up display device as shown in FIG.

<Third Embodiment>
FIG. 6 is a diagram showing an example of the configuration of a display device according to the third embodiment of the present invention.
The display device shown in FIG. 6 is obtained by replacing the second lens 42 as the intermediate optical system in the display device shown in FIG. The second lens 44 is the same as the component with the same reference numeral in FIG.

In the display device shown in FIG. 6, since the distance from the reflecting surface 33 to the second screen 52 is longer than the distance from the reflecting surface 33 to the first screen 51, the focal length of the light incident on the first screen 51 is set. While the 1st lens 41 is shortened, the 2nd lens 44 is lengthening the focal distance of the light ray which injects into the 2nd screen 52. FIG.

The display device according to the present embodiment can obtain the same effects as those of the display device according to the first embodiment, and can be applied to a head-up display device as shown in FIG. Further, according to the present embodiment, when the distance between the first screen 51 and the second screen 52 is large, it is not necessary to extremely increase the refractive power of each intermediate optical system (41, 44). With a simple configuration, it is possible to easily focus on each screen.

<Fourth Embodiment>
FIG. 7 is a diagram showing an example of the configuration of a display device according to the fourth embodiment of the present invention.
The display device shown in FIG. 7 is obtained by omitting the second lens 42 in the display device shown in FIG. A light beam incident on the second screen 52 is focused by setting an optical system (such as a collimator lens) built in the light source 20. Since the first screen 51 has a shorter distance from the light source 20 than the second screen 52, the light beam incident on the first screen 51 is focused by the first lens 41 having a positive refractive power. As described above, when the distance between the first screen 51 and the second screen 52 is relatively short, the two screens (51, 52) can be focused by one intermediate optical system (41).

Also in the display device according to the present embodiment, it is possible to obtain the same effect as the display device according to the first embodiment.

<Fifth Embodiment>
FIG. 8 is a diagram showing an example of the configuration of a display device according to the fourth embodiment of the present invention.
In the display device shown in FIG. 8, the first lens 41 in the display device shown in FIG. 1 is omitted, and the second lens 42 is replaced with a second lens 44. The second lens 44 is the same as the component with the same reference numeral in FIG.

The focus of the light beam incident on the first screen 51 is adjusted by the setting of an optical system (such as a collimator lens) built in the light source 20. Since the second screen 52 has a longer distance from the light source 20 than the first screen 51, the light beam incident on the second screen 52 is focused by the second lens 44 having a negative refractive power. Thus, when the distance between the first screen 51 and the second screen 52 is relatively short, the two screens (51, 52) can be focused by one intermediate optical system (44).

Also in the display device according to the present embodiment, it is possible to obtain the same effect as the display device according to the first embodiment. In addition, according to the present embodiment, the number of intermediate optical systems used can be reduced, so that the configuration can be simplified.

Although the present invention has been described with reference to the above embodiment, the present invention is not limited to the above embodiment, and can be improved or changed within the scope of the purpose of the improvement or the idea of the present invention.

As described above, the display device according to the present invention is useful for a head-up display device for a vehicle, and is suitable for displaying different images at a plurality of display positions.

DESCRIPTION OF SYMBOLS 10 Display apparatus 20 Light source 30 Scanner (scanning means)
33 Reflecting surface 41 First lens (intermediate optical system)
42 Second lens (intermediate optical system)
43 First lens (intermediate optical system)
44 Second lens (intermediate optical system)
51 First screen 52 Second screen 60 Projection lens (projection optical system)
60c Optical axis 110 Display device 120 Laser light source 130 Scanner (scanning means)
132 Rotating shaft 133 Reflecting surface 141 First lens (intermediate optical system)
142 Second lens (intermediate optical system)
151 First screen 152 Second screen 161 First projection mirror (projection optical system)
162 Second projection mirror (projection optical system)
A1, A2 Scanning area D1, D2, D11, D12 Reflection direction E Eye f1, f2, f3 Focal length I1, I2 Virtual image L distance P1, P2 Projected light S1, S2 distance

Claims

A display device that displays an image corresponding to an intermediate image formed on each of two screens, and a light source that emits light;
A scanner that selectively reflects light from the light source toward one of the two screens and scans the screen with the reflected light;
A projection optical system for projecting an image corresponding to the intermediate image formed on the screen by scanning light beams of the scanner;
Arranged in at least one of an optical path from the scanner to one of the screens and an optical path from the scanner to the other of the screens, and at least one for focusing a light beam from the scanner on the screen on the arranged optical path. With two intermediate optical systems,
The display device, wherein the light from the scanner is focused on each of the two screens.
The display according to claim 1, wherein the intermediate optical system having a positive refractive power is disposed in an optical path from the scanner to one of the screens and an optical path from the scanner to the other of the screens. apparatus.
The length of the optical path from the scanner to one of the screens is relatively different from the length of the optical path from the scanner to the other screen,
The intermediate optical system disposed in the relatively short optical path has a larger positive refractive power than the intermediate optical system disposed in the relatively long optical path. Display device.
2. The display according to claim 1, wherein the intermediate optical system having negative refractive power is disposed in an optical path from the scanner to one of the screens and an optical path from the scanner to the other of the screens. apparatus.
The length of the optical path from the scanner to one of the screens is relatively different from the length of the optical path from the scanner to the other screen,
5. The intermediate optical system disposed in the relatively long optical path has a larger negative refractive power than the intermediate optical system disposed in the relatively short optical path. Display device.
The intermediate optical system having a positive refractive power is arranged in an optical path from the scanner to one of the screens,
The display device according to claim 1, wherein the intermediate optical system having a negative refractive power is disposed in an optical path from the scanner to the other screen.
The display according to claim 6, wherein the optical path in which the intermediate optical system having the positive refractive power is arranged is shorter than the optical path in which the intermediate optical system having the negative refractive power is arranged. apparatus.
The intermediate optical system disposed in the optical path from the scanner to the one screen and the intermediate optical system disposed in the optical path from the scanner to the other screen have a common optical axis,
The display device according to claim 2, wherein the scanner reflects a light beam from the light source on a reflection surface that is rotatable around an axis that passes through the common optical axis. .
The display device according to claim 1, wherein the intermediate optical system is disposed in any one of an optical path from the scanner to one of the screens and an optical path from the scanner to the other of the screens.
The intermediate optical system has a positive refractive power,
The display device according to claim 9, wherein the optical path in which the intermediate optical system having the positive refractive power is arranged is shorter than the optical path in which the intermediate optical system is not arranged.
The intermediate optical system has a negative refractive power,
The display device according to claim 9, wherein the optical path in which the intermediate optical system having the negative refractive power is disposed is longer than the optical path in which the intermediate optical system is not disposed.
The scanner reflects a light beam from the light source on a rotating reflecting surface,
The distance from the reflecting surface to the intermediate optical system and the distance from the intermediate optical system to the screen are both equal to the focal length of the intermediate optical system. The display device according to one item.