OPTICAL DEVICE

An optical device includes: a display; an optical element that includes a first face and a second face facing the first face, the optical element receiving light from the display through the first face, reflecting the received light on the second face, and emitting the reflected light through the first face; a housing that accommodates the display and the optical element; and a fixing structure that fixes the optical element by holding the optical element from different sides of the optical element.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is based on and claims priority of Japanese Patent Application No. 2022-042245 filed on Mar. 17, 2022, and Japanese Patent Application No. 2022-135020 filed on Aug. 26, 2022.

FIELD

The present disclosure relates to optical devices.

BACKGROUND

An optical device is known to include an optical element that reflects light emitted from a display. As an example of such an optical device, Patent Literature (PTL) 1 discloses a head-up display device including an imaging unit and a virtual image optical system that causes light emitted from the imaging unit to be reflected by a windshield or a combiner to display a virtual image in the front of a vehicle.

CITATION LIST

Patent Literature

SUMMARY

However, the head-up display device according to PTL 1 can be improved upon.

In view of this, the present disclosure provides an optical device capable of improving upon the above related art.

In accordance with an aspect of the present disclosure, an optical device includes: a display; an optical element that includes a first face and a second face facing the first face, the optical element receiving light from the display through the first face, reflecting the received light on the second face, and emitting the reflected light through the first face; a housing that accommodates the display and the optical element; and a fixing structure that fixes the optical element by holding the optical element from different sides of the optical element.

An optical device according to the aspect of the present disclosure is capable of improving upon the above related art.

DESCRIPTION OF EMBODIMENTS

Here, in a case where an optical device includes an optical element fixed by press fitting or using adhesive and where light emitted from a display enters the optical element, is reflected by the optical element, and is then emitted from the optical element, deformation of the optical element caused by heat, vibration, and the like easily leads to damage to the optical element. This easily reduces the quality of the image displayed by the optical device.

In view of this, the present disclosure provides an optical device capable of preventing a reduction in the image quality.

In accordance with an aspect of the present disclosure, an optical device includes: a display; an optical element that includes a first face and a second face facing the first face, the optical element receiving light from the display through the first face, reflecting the received light on the second face, and emitting the reflected light through the first face; a housing that accommodates the display and the optical element; and a fixing structure that fixes the optical element by holding the optical element from different sides of the optical element.

With this, the optical element can be fixed by being held from different sides and thus is at less risk of damage compared with a case where the optical element is fixed by press fitting or using adhesive. This prevents a reduction in the quality of the image displayed by the optical device.

It is possible that the optical element includes a side face that links the first face and the second face, and the fixing structure includes a first face presser provided for the housing and at least one of a second face presser or a side face presser, the first face presser pressing an edge portion of the optical element from a side where the first face lies when the optical element is viewed from the side where the first face lies, the second face presser pressing the optical element from a side where the second face lies, the side face presser pressing the optical element from a side where the side face lies.

With this, the optical element can be fixed by being held between the first face presser and at least one of the second face presser or the side face presser. Moreover, the edge portion of the optical element can be covered by the first face presser when the optical element is viewed from the side where the first face lies. This prevents stray light, if any, coming from the edge portion from affecting the image displayed by the optical device, thereby preventing a reduction in the quality of the image displayed by the optical device.

It is also possible that the side face includes a first side portion and a second side portion that faces the first side portion, the fixing structure includes the side face presser, and the side face presser includes a first side portion presser that presses the optical element from a side where the first side portion lies and a second side portion presser that presses the optical element from a side where the second side portion lies.

With this, the optical element can be fixed by being held from different sides while damage to the second face that reflects light is prevented. This further prevents a reduction in the quality of the image displayed by the optical device.

It is further possible that the second side portion is inclined with respect to the first side portion to be away from the first side portion as the second side portion is closer to the first face than the second face, the first side portion presser presses the first side portion, and the second side portion presser presses the second side portion.

With this, when the first side portion and the second side portion are pressed, the optical element can also be pressed toward the first face from the side where the second face lies. Thus, the optical element can be fixed by being held by the first face presser, the first side portion presser, and the second side portion presser. Accordingly, the optical element can be fixed by being held from different sides while damage to the second face that reflects light is further prevented. This further prevents a reduction in the quality of the image displayed by the optical device.

It is still further possible that the first side portion is an upper face portion of the optical element when the optical element is viewed from the side where the first face lies, and the first side portion presser presses the first side portion from above the optical element when the optical element is viewed from the side where the first face lies.

With this, the first side portion presser protrudes downward to press the first side portion when the optical element is viewed from the side where the first face lies. This minimizes the depth of the first side portion presser, thereby reducing the depth of the housing.

It is still further possible that the first side portion is an upper face portion of the optical element when the optical element is viewed from the side where first face lies, the side face includes a third side portion and a fourth side portion, the third side portion being connected to a left end of the first side portion and located further leftward as the third side portion is closer to the second side portion when the optical element is viewed from the side where the first face lies, the fourth side portion being connected to a right end of the first side portion and located further rightward as the fourth side portion is closer to the second side portion when the optical element is viewed from the side where the first face lies, and the side face presser includes at least one of a third side portion presser that presses the third side portion from above the optical element when the optical element is viewed from the side where the first face lies or a fourth side portion presser that presses the fourth side portion from above the optical element when the optical element is viewed from the side where the first face lies.

With this, the third side portion presser protrudes downward to press the third side portion when the optical element is viewed from the side where the first face lies. This minimizes the depth of the third side portion presser, thereby reducing the depth of the housing. Moreover, the fourth side portion presser protrudes downward to press the fourth side portion when the optical element is viewed from the side where the first face lies. This minimizes the depth of the fourth side portion presser, thereby reducing the depth of the housing. Furthermore, the optical element can be easily fixed in all directions including the front-back, up-down, and left-right directions of the optical element when the optical element is viewed from the side where the first face lies. This eliminates or minimizes the effect of thermal expansion and vibration of the optical element in all directions on the image.

It is still further possible that the fixing structure includes the second face presser, and the second face presser is in surface contact with the second face to press the second face.

This prevents a pressing force from being concentrated on a part of the second face. Accordingly, the optical element can be fixed by being held (sandwiched) from different sides while damage to the second face that reflects light is prevented. This further prevents a reduction in the quality of the image displayed by the optical device.

It is still further possible that the first face presser includes three or more edge pressers each pressing an edge portion of the first face.

This prevents displacement of the optical element, thereby further preventing a reduction in the quality of the image displayed by the optical device.

It is still further possible that the first face presser presses an edge portion of the first face around an entire circumference of the first face.

This prevents displacement of the optical element, thereby further preventing a reduction in the quality of the image displayed by the optical device. Moreover, even if stray light is produced at the edge portion of the first face, the stray light can be prevented from affecting the image displayed by the optical device. This prevents a reduction in the quality of the image displayed by the optical device.

It is still further possible that the fixing structure includes the second face presser, and the first face presser and the second face presser mutually hold the optical element in directions in which the first face and the second face face each other.

This prevents deformation of the optical element caused when the optical element is held (sandwiched) from different sides, thereby further preventing a reduction in the quality of the image displayed by the optical device.

It is still further possible that at least one of the second face presser or the side face presser has flexibility.

This prevents damage to the optical element, thereby further preventing a reduction in the quality of the image displayed by the optical device.

It is still further possible that the fixing structure includes the second face presser, a member with a screw hole, and a screw that presses the second face presser toward the optical element while fitted in the screw hole, and the second face presser presses the optical element by being pressed toward the optical element by the screw.

This prevents displacement of the optical element, thereby further preventing a reduction in the quality of the image displayed by the optical device.

Moreover, the second face presser may be integral to the housing.

This prevents a reduction in the quality of the image displayed by the optical device while preventing an increase in the number of parts.

Moreover, a substrate held and fixed between the screw and the member while the screw is fitted in the screw hole may be provided.

This allows the substrate to be provided without an increase in the number of parts.

It is still further possible that the fixing structure includes the second face presser, and the second face presser includes one edge presser that presses one edge portion of the second face, an other edge presser that presses an other edge portion of the second face, and a covering presser that presses the second face while covering the second face between the one edge presser and the other edge presser.

This prevents displacement of the optical element, thereby further preventing a reduction in the quality of the image displayed by the optical device.

It is still further possible that the optical element includes at least one of a first recess provided at an edge portion of the first face or a first protrusion provided at the edge portion of the first face, and the housing includes at least one of a second protrusion that engages with the first recess or a second recess that engages with the first protrusion.

With this, the optical element can be easily positioned relative to the housing. This easily prevents a reduction in the quality of the image displayed by the optical device.

It is still further possible that the housing includes a body that accommodates the optical element and cover that is attached to the body and covers the second face of the optical element, and at least one of the second face presser or the side face presser is provided for the cover.

With this, the optical element can be fixed by being held from different sides as the cover is attached to the body. This easily prevents a reduction in the quality of the image displayed by the optical device.

It is still further possible that the fixing structure includes the side face presser, and the side face presser includes an upper presser and at least one of a left presser or a right presser, the upper presser pressing the optical element using an elastic force from above, the left presser pressing the optical element using an elastic force from a left, the right presser pressing the optical element using an elastic force from a right, when the optical element is viewed from the side where the first face lies.

This prevents damage to the optical element even if, for example, the optical element expands, thereby further preventing a reduction in the quality of the image displayed by the optical device.

It is still further possible that the first face includes a curved portion and a flat portion connected to an edge portion of the curved portion, and the first face presser presses the flat portion.

With this, even if the first face includes the curved portion, the optical element can be fixed by being held (sandwiched) from different sides when the flat portion is pressed. This easily prevents a reduction in the quality of the image displayed by the optical device.

It is still further possible that the optical device further includes: a protecting member provided at at least one of a point between the first face and the first face presser, a point between the second face and the second face presser, or a point between the side face and the side face presser.

This prevents damage to the optical element, thereby further preventing a reduction in the quality of the image displayed by the optical device.

It is still further possible that the optical device further includes: a light absorbing member provided at least in a part of the side face.

This prevents the light entering the first face from being reflected from the side face, thereby further preventing a reduction in the quality of the image displayed by the optical device.

It is still further possible that the optical device further includes: a metallic multilayer including a plurality of laminated metallic layers and disposed on the second face.

With this, even if the outermost layer of the metallic multilayer breaks, the remaining metallic layers can prevent damage to the second face. In addition, the light entering the first face can be easily reflected from the second face. This further prevents a reduction in the quality of the image displayed by the optical device.

The following embodiments are specific examples of the present disclosure. The numerical values, shapes, materials, elements, arrangement and connection configuration of the elements, steps, the order of the steps, etc., described in the following embodiments are merely examples, and are not intended to limit the present disclosure. Among elements in the following embodiments, those not described in any one of the independent claims indicating the broadest concept of the present disclosure are described as optional elements.

Moreover, in the following embodiments, terms such as “parallel” and “orthogonal” may be used to indicate relative orientations of two directions. These terms, however, may be different from the orientations in the strict sense. For example, an expression of “two directions are parallel” indicates not only that the two directions are exactly parallel but that the two directions are substantially parallel, that is, for example, there may be a difference of a few percent between the two directions unless otherwise noted.

Optical paths illustrated in the drawings in the following embodiments are given to indicate the principle concepts, and do not necessarily reflect actual optical paths.

FIG.1is a schematic diagram of optical device10according to Embodiment 1 installed in vehicle1. InFIG.1, vehicle1and housing20are illustrated in cross section.

As illustrated inFIG.1, optical device10displays an image by reflecting light emitted from display40. In this embodiment, optical device10is installed inside the cabin of vehicle1. For example, optical device10displays an image captured by a camera that captures the image in the rear of vehicle1. This allows driver2of vehicle1to visually check the state in the rear of vehicle1by looking at optical device10(see a broken line arrow inFIG.1).

Note that, for example, optical device10may display an image indicating the speed of vehicle1, results of detection of an object approaching vehicle1, information about navigation from the current location of vehicle1to the destination, or the like.

FIG.2is a schematic diagram of optical device10inFIG.1. InFIG.2, housing20and the like are illustrated in cross section.

Housing20accommodates display40, reflective mirror60, and optical element80. In this embodiment, housing20is suspended from the roof of vehicle1. Housing20includes body21, emission portion22, and cover23.

Emission portion22allows light emitted from display40to be guided to the outside of housing20. In this embodiment, emission portion22is provided such that light is emitted from display40, then reflected from reflective mirror60to enter optical element80, and reflected from optical element80to be emitted from optical element80through emission portion22. Emission portion22is a through-hole that connects the spaces inside and outside body21.

Cover23is attached to body21to cover second face82of optical element80. That is, cover23covers second face82of optical element80when it is attached to body21. In this embodiment, cover23is attached to body21with screws24(seeFIG.8, for example). Note that, for example, cover23may be attached to body21by engaging with body21.

Display40radiates light representing an image. For example, display40radiates light representing the image captured by the camera that captures the image in the rear of vehicle1. For example, display40is implemented by including an LCD (Liquid Crystal Display), an organic EL (Electro Luminescence) display, or a micro LED (Light Emitting Diode) display.

Reflective mirror60reflects the light emitted from display40toward optical element80. Specifically, reflective mirror60reflects the light emitted from display40toward first face81of optical element80.

Optical element80includes first face81, second face82that faces first face81, and side face83that links first face81and second face82. Optical element80is provided such that light is emitted from display40, then enters optical element80through first face81, and is reflected from second face82to be emitted from optical element80through first face81. In this embodiment, the light emitted from display40is reflected by reflective mirror60to enter optical element80through first face81. The light entering optical element80through first face81is reflected from second face82to be guided to the outside of optical element80through first face81. The light guided to the outside of optical element80through first face81travels to the outside of housing20through emission portion22(see thick line arrows inFIG.2).

First face81allows the light emitted from display40to enter and the light reflected from second face82to exit. In this embodiment, first face81is a flat surface. In this embodiment, first face81has a horizontally oblong shape when optical element80is viewed from a side where first face81lies.

Second face82reflects the light, emitted from display40and entering through first face81, toward first face81. In this embodiment, second face82is a flat surface. In this embodiment, second face82has a horizontally oblong shape when optical element80is viewed from the side where first face81lies. In this embodiment, second face82is slightly smaller than first face81.

For example, second face82is parallel to first face81. Note that, for example, second face82may be inclined with respect to first face81such that the thickness of an upper part of optical element80differs from the thickness of a lower part of optical element80when optical element80is viewed from the side where first face81lies.

Note that, for example, first face81may be a curved surface recessed toward second face82, and second face82may be a curved surface protruding away from first face81. That is, for example, first face81and second face82may be curved surfaces curved away from a side, of optical element80, at which the light emitted from display40enters (away from the incident side). In this case, for example, first face81and second face82may be freeform surfaces using polynomial functions or the like.

Side face83links first face81and second face82. Specifically, side face83is connected to the edge portion of first face81and the edge portion of second face82to link the edge portion of first face81and the edge portion of second face82. Side face83has a ring shape along the edge portion of first face81and the edge portion of second face82. Side face83includes first side portion84, second side portion85, third side portion101(seeFIG.8, for example), and fourth side portion102.

In this embodiment, first side portion84in side face83links the upper edge portion of first face81and the upper edge portion of second face82when optical element80is viewed from the side where first face81lies. In this embodiment, first side portion84is an upper face portion of optical element80when optical element80is viewed from the side where first face81lies.

Second side portion85faces first side portion84. In this embodiment, second side portion85links the lower edge portion of first face81and the lower edge portion of second face82when optical element80is viewed from the side where first face81lies. In this embodiment, second side portion85is a lower face portion of optical element80when optical element80is viewed from the side where first face81lies.

In this embodiment, second side portion85is inclined with respect to first side portion84to be away from first side portion84as second side portion85is closer to first face81than second face82. That is, in this embodiment, first side portion84is inclined with respect to second side portion85to be away from second side portion85as first side portion84is closer to first face81than second face82.

Third side portion101is connected to the left end of first side portion84and located further leftward as third side portion101is closer to second side portion85when optical element80is viewed from the side where first face81lies. In this embodiment, third side portion101is curved.

Fourth side portion102is connected to the right end of first side portion84and located further rightward as fourth side portion102is closer to second side portion85when optical element80is viewed from the side on which first face81lies. In this embodiment, fourth side portion102is curved.

For example, optical element80is made of light-transmitting resin or a light-transmitting material, such as glass.

Light-transmitting cover110is disposed at emission portion22and allows the light emitted from optical element80to pass therethrough. Specifically, light-transmitting cover110is disposed at emission portion22and allows the light emitted through first face81of optical element80to pass therethrough. For example, light-transmitting cover110is made of light-transmitting glass or light-transmitting resin.

First face presser121is provided for housing20and presses the edge portion of optical element80from the side where first face81lies when optical element80is viewed from the side where first face81lies. In this embodiment, first face presser121presses the edge portion of first face81. In this embodiment, first face presser121is in contact with the edge portion of first face81. Note that, for example, first face presser121may not be in contact with the edge portion of first face81and may press the edge portion of first face81through other members. First face presser121includes one edge presser123and other edge presser124.

One edge presser123presses one edge portion86of first face81. In this embodiment, one edge presser123is in contact with edge portion86. In this embodiment, edge portion86is the upper edge portion of first face81when optical element80is viewed from the side where first face81lies. In this embodiment, one edge presser123is integral to body21and protrudes downward from the inner surface of body21when optical element80is viewed from the side where first face81lies.

Other edge presser124presses other edge portion87of first face81. In this embodiment, other edge presser124is in contact with edge portion87. In this embodiment, edge portion87is the lower edge portion of first face81when optical element80is viewed from the side where first face81lies. In this embodiment, other edge presser124is integral to body21and protrudes upward from the inner surface of body21when optical element80is viewed from the side where first face81lies.

Side face presser122presses optical element80from a side where side face83lies. In this embodiment, side face presser122presses side face83. In this embodiment, side face presser122is in contact with side face83. Note that, for example, side face presser122may not be in contact with side face83and may press side face83through other members. Side face presser122includes first side portion presser125and second side portion presser126.

First side portion presser125presses optical element80from a side where first side portion84lies. In this embodiment, first side portion presser125is in contact with first side portion84and presses first side portion84.

In this embodiment, first side portion presser125is provided for cover23. For example, first side portion presser125is integral to cover23. First side portion presser125protrudes toward optical element80and presses first side portion84as cover23is attached to body21.

For example, first side portion presser125has flexibility. Specifically, for example, first side portion presser125has flexibility higher than that of optical element80. That is, for example, first side portion presser125is more flexible than optical element80. For example, a part of first side portion presser125brought into contact with optical element80is formed of a flexible member. Moreover, for example, first side portion presser125is composed of a flexible member. For example, the flexible member is more flexible than optical element80and is made of rubber, fabric, or the like.

Second side portion presser126presses optical element80from a side where second side portion85lies. In this embodiment, second side portion presser126is in contact with second side portion85and presses second side portion85.

In this embodiment, second side portion presser126is provided for body21and is integral to body21.

In this embodiment, optical element80can be held between first side portion presser125and second side portion presser126from the sides where side face83lies. Moreover, in this embodiment, second side portion85is inclined with respect to first side portion84to be away from first side portion84as second side portion85is closer to first face81than second face82. Accordingly, when first side portion84and second side portion85are respectively pressed by first side portion presser125and second side portion presser126, optical element80is also pressed toward first face81. Thus, optical element80can be held by one edge presser123and other edge presser124and by first side portion presser125and second side portion presser126. In this manner, fixing structure120in this embodiment fixes optical element80by holding optical element80nwith one edge presser123and other edge presser124and with first side portion presser125and second side portion presser126.

Optical device10according to Embodiment 1 has been described above.

As described above, optical device10according to Embodiment 1 includes display40, optical element80including first face81and second face82that faces first face81, housing20accommodating display40and optical element80, and fixing structure120fixing optical element80by holding optical element80. Light is emitted from display40, enters optical element80through first face81, and then reflected from second face82to be emitted from optical element80through first face81.

With this, optical element80can be fixed by being held from different sides and thus is at less risk of damage compared with a case where optical element80is fixed by press fitting or using adhesive. This prevents a reduction in the quality of the image displayed by optical device10.

Moreover, optical element80includes side face83that links first face81and second face82, and fixing structure120includes first face presser121provided for housing20and side face presser122. When optical element80is viewed from the side where first face81lies, first face presser121presses the edge portion of optical element80from the side where first face81lies, and side face presser122presses optical element80from the side where side face83lies.

With this, optical element80can be held and fixed between first face presser121and side face presser122. Moreover, the edge portion of optical element80can be covered by first face presser121when optical element80is viewed from the side where first face81lies. This prevents stray light, if any, coming from the edge portion from affecting the image displayed by optical device10, thereby preventing a reduction in the quality of the image displayed by optical device10.

Moreover, side face83includes first side portion84and second side portion85that faces first side portion84, and fixing structure120includes side face presser122. Side face presser122includes first side portion presser125that presses optical element80from the side where first side portion84lies and second side portion presser126that presses optical element80from the side where second side portion85lies.

With this, optical element80can be held from different sides to be fixed while damage to second face82that reflects light is prevented. This further prevents a reduction in the quality of the image displayed by optical device10.

Moreover, second side portion85is inclined with respect to first side portion84to be away from first side portion84as second side portion85is closer to first face81than second face82, and first side portion presser125and second side portion presser126respectively press first side portion84and second side portion85.

With this, when first side portion84and second side portion85are pressed, optical element80is also pressed toward first face81from a side where second face82lies. Thus, optical element80can be held and fixed among first face presser121, first side portion presser125, and second side portion presser126. Accordingly, optical element80can be held from different sides to be fixed while damage to second face82that reflects light is further prevented. This further prevents a reduction in the quality of the image displayed by optical device10.

Moreover, housing20includes body21that accommodates optical element80and cover23that is attached to body21to cover second face82of optical element80, and cover23is provided with side face presser122.

With this, optical element80can be held from different sides to be fixed as cover23is attached to body21. This easily prevents a reduction in the quality of the image displayed by optical device10.

FIG.3is a schematic diagram of optical device10xaccording to Variation 1 of Embodiment 1. Note that, in Variation 1, elements identical to those in Embodiment 1 will be referenced by the same designators, and the detailed explanations will be omitted. The distinctive configuration in Variation 1 is that housing20xis dividable in the vertical direction inFIG.3and that first side portion presser125xis disposed on the upper half of housing20x.

Optical device10xincludes housing20xinstead of housing20and fixing structure120xinstead of fixing structure120. Housing20xdoes not include cover23, and body21xof housing20xincludes first member27x, which is an upper part, and second member28x, which is a lower part. Side face presser122xof fixing structure120xincludes first side portion presser125xinstead of first side portion presser125.

Specifically, first, inFIG.3, housing20xis vertically dividable into an upper part and a lower part substantially at its midsection in the height direction. That is, engaging the upper and lower parts of housing20x(first member27xand second member28x) with each other forms the overall shape of housing20x. Note that the upper and lower parts of housing20x(first member27xand second member28x) may be fixed by, but not limited in particular to, screws (not illustrated), snap fitting, or bonding.

Optical element80is fixed by being held from different sides by housing20xthat can be vertically divided. For example, the upper part of housing20x(first member27x) is placed on the lower part of housing20x(second member28x) with optical element80fitted in the lower part. The upper and lower parts of housing20x(first member27xand second member28x) are then fixed to each other. Thus, optical element80is fixed to housing20x. At this moment, the upper part of housing20x(first member27x) is provided with first side portion presser125xthat has flexibility. First side portion presser125xis disposed at a position where first side portion presser125xabuts on first side portion84of optical element80when the upper part of housing20x(first member27x) is fixed to the lower part of housing20x(second member28x). Accordingly, fixing the upper part of housing20x(first member27x) to the lower part of housing20x(second member28x) with optical element80fitted in the lower part of housing20x(second member28x) causes first side portion presser125xto abut on first side portion84. This fixes optical element80to housing20x. In this manner, first side portion presser125xpresses first side portion84from above optical element80when optical element80is viewed from the side where first face81lies.

Here, first side portion84is inclined with respect to both the lateral direction (that is, the front-back direction of housing20x) and the vertical direction (that is, the height direction of housing20x) inFIG.3. Accordingly, when first side portion presser125xabuts on first side portion84, optical element80receives a pressing force perpendicular to the inclined surface of first side portion84. The pressing force is divided into components acting in the front-back direction and the height direction of housing20x. As a result, optical element80is held by first side portion presser125xin the front-back direction and the height direction of housing20x. Accordingly, thermal expansion of optical element80and vibration of the vehicle in the front-back direction and the height direction are absorbed by first side portion presser125xthat has flexibility.

Furthermore, first side portion presser125xis disposed substantially parallel to the height direction of housing20x. This reduces the depth of housing20xcompared with the configuration in which first side portion presser125is disposed substantially parallel to the front-back direction of housing20as illustrated inFIG.2.

Optical device10xaccording to Variation 1 has been described above.

As described above, in optical device10xaccording to Variation 1, first side portion84is the upper face portion of optical element80when optical element80is viewed from the side where first face81lies, and first side portion presser125xpresses first side portion84from above optical element80when optical element80is viewed from the side where first face81lies.

With this, first side portion presser125xprotrudes downward to press first side portion84when optical element80is viewed from the side where first face81lies. This minimizes the depth of first side portion presser125x, thereby reducing the depth of housing20x.

Furthermore, the thermal expansion of optical element80and the vibration of the vehicle in the front-back direction and the height direction of housing20xare absorbed by first side portion presser125x. This eliminates or minimizes the effect on the image.

FIG.4is a schematic diagram of optical device10yaccording to Variation 2 of Embodiment 1. Note that, in Variation 2, elements identical to those in Embodiment 1 will be referenced by the same designators, and the detailed explanations will be omitted. The distinctive configuration in Variation 2 is that housing20yis dividable in the vertical direction inFIG.4and that a third side portion presser (not illustrated) disposed on the upper half of housing20ypresses third side portion101from above optical element80while fourth side portion presser135ydisposed on the upper half of housing20ypresses fourth side portion102from above optical element80.

Optical device10yincludes housing20yinstead of housing20and fixing structure120yinstead of fixing structure120. Housing20ydoes not include cover23, and body21yof housing20yincludes first member27y, which is an upper part, and second member28y, which is a lower part. Side face presser122yof fixing structure120yincludes the third side portion presser and fourth side portion presser135yinstead of first side portion presser125. Note that, for example, side face presser122ymay further include first side portion presser125x. The third side portion presser is symmetrical with fourth side portion presser135ywhen optical element80is viewed from the side where first face81lies.

Specifically, first, the configuration in which housing20yis vertically dividable and a method of fixing both parts (first member27yand second member28y) are identical to those of housing20xin Variation 1. Next, the configuration in which optical element80is held and fixed between the upper and lower parts of housing20yis also the same as that in Variation 1. In Variation 2, however, the third side portion presser with flexibility abuts on third side portion101of optical element80, and fourth side portion presser135ywith flexibility abuts on fourth side portion102of optical element80. Note that, for example, third side portion101can be defined as a part, under the upper end, extending from the upper end to the left end of optical element80when optical element80is viewed from the side where first face81lies, whereas fourth side portion102can be defined as a part, under the upper end, extending from the upper end to the right end of optical element80when optical element80is viewed from the side where first face81lies. In other words, third side portion101and fourth side portion102are diagonally upper parts when optical element80is viewed from the side where first face81lies.

Here, third side portion101and fourth side portion102are inclined with respect to both the front-back direction and the height direction of housing20yinFIG.4and also to the left-right direction (direction perpendicular to the page inFIG.4) when optical element80is viewed from the side where first face81lies. Accordingly, when the third side portion presser abuts on third side portion101, optical element80receives a pressing force perpendicular to the inclined surface of third side portion101. Moreover, when fourth side portion presser135yabuts on fourth side portion102, optical element80receives a pressing force perpendicular to the inclined surface of fourth side portion102. These pressing forces are divided into components acting in the front-back direction, the height direction, and the left-right direction of housing20y. As a result, optical element80is held by the third side portion presser and fourth side portion presser135yin the front-back direction, the height direction, and the left-right direction of housing20y. Accordingly, thermal expansion of optical element80and vibration of the vehicle in the front-back direction, the height direction, and the left-right direction are absorbed by the third side portion presser and fourth side portion presser135ythat have flexibility.

Furthermore, as illustrated inFIG.4, fourth side portion presser135yis slightly inclined with respect to the height direction of housing20y. This reduces the depth of housing20ycompared with the configuration in which first side portion presser125is disposed substantially parallel to the front-back direction of housing as illustrated inFIG.2. The same applies to the third side portion presser.

Optical device10yaccording to Variation 2 has been described above.

As described above, in optical device10yaccording to Variation 2, first side portion84is the upper face portion of optical element80when optical element80is viewed from the side where first face81lies. Side face83includes third side portion101and fourth side portion102. Third side portion101is connected to the left end of first side portion84and located further leftward as third side portion101is closer to second side portion85when optical element80is viewed from the side where first face81lies, whereas fourth side portion102is connected to the right end of first side portion84and located further rightward as fourth side portion102is closer to second side portion85when optical element80is viewed from the side where first face81lies. Side face presser122yincludes at least one of the third side portion presser that presses third side portion101from above optical element80when optical element80is viewed from the side where first face81lies or fourth side portion presser135ythat presses fourth side portion102from above optical element80when optical element80is viewed from the side where first face81lies.

With this, the third side portion presser protrudes downward to press third side portion101when optical element80is viewed from the side where first face81lies. This minimizes the depth of the third side portion presser, thereby reducing the depth of housing20y. Moreover, fourth side portion presser135yprotrudes downward to press fourth side portion102when optical element80is viewed from the side where first face81lies. This minimizes the depth of fourth side portion presser135y, thereby reducing the depth of housing20y. Furthermore, optical element80can be easily fixed in all directions including the front-back, up-down, and left-right directions of optical element80when optical element80is viewed from the side where first face81lies. This eliminates or minimizes the effect of the thermal expansion and vibration of optical element80in all directions on the image.

Note that the configuration is not limited to that in which third side portion presser abuts on third side portion101of optical element80while fourth side portion presser135yabuts on fourth side portion102of optical element80, and only the third side portion presser or fourth side portion presser135ymay be provided. Also in this case, the effect of the thermal expansion and vibration of optical element80in all directions on the image can be eliminated or minimized.

FIG.5is a schematic diagram of optical device10aaccording to Embodiment 2. InFIG.5, housing20and the like are illustrated in cross section. Optical device10amainly differs from optical device10in further including metallic multilayer88.

Metallic multilayer88is a reflective member for facilitating reflection of light from second face82. Metallic multilayer88is formed on second face82. In this embodiment, metallic multilayer88is formed on the entire surface of second face82. Metallic multilayer88includes a plurality of laminated metallic layers. For example, the plurality of metallic layers include aluminum layers or the like.

Optical device10aaccording to Embodiment 2 has been described above.

As described above, optical device10aaccording to Embodiment 2 includes metallic multilayer88including the plurality of laminated metallic layers and formed on second face82.

With this, even if the outermost layer of metallic multilayer88breaks, the remaining metallic layers can prevent damage to second face82. In addition, the light entering first face81can be easily reflected from second face82. This further prevents a reduction in the quality of the image displayed by optical device10a.

FIG.6is a schematic diagram of optical device10baccording to Embodiment 3. InFIG.6, housing20and the like are illustrated in cross section. Optical device10bmainly differs from optical device10ain further including protecting member160.

As illustrated inFIG.6, protecting member160is disposed between first side portion presser125and first side portion84. Protecting member160protects optical element80. In this embodiment, protecting member160prevents first side portion presser125from coming into direct contact with first side portion84to protect first side portion84. For example, protecting member160is more flexible than optical element80and first side portion presser125, and is made of rubber, fabric, or the like.

For example, protecting member160may be disposed between second side portion presser126and second side portion85and between first face81and first face presser121.

Moreover, for example, optical device10bmay not be provided with metallic multilayer88.

Optical device10baccording to Embodiment 3 has been described above.

As described above, optical device10baccording to Embodiment 3 includes protecting member160disposed between side face83(first side portion84) and side face presser122(first side portion presser125).

This prevents damage to optical element80, thereby further preventing a reduction in the quality of the image displayed by optical device10b.

FIG.7is a schematic diagram of optical device10caccording to Embodiment 4. InFIG.7, housing20, light absorbing member180, and the like are illustrated in cross section. Optical device10cmainly differs from optical device10ain further including light absorbing member180.

As illustrated inFIG.7, light absorbing member180is disposed on side face83. In this embodiment, light absorbing member180is disposed on the entire circumference of side face83. Light absorbing member180absorbs light. For example, the color of light absorbing member180is black.

Note that, for example, light absorbing member180may not be disposed on the entire circumference of side face83but only on a part of side face83.

Moreover, for example, optical device10cmay not be provided with metallic multilayer88.

Optical device10caccording to Embodiment 4 has been described above.

As described above, optical device10caccording to Embodiment 4 includes light absorbing member180disposed at least on a part of side face83.

This prevents the light entering first face81from being reflected from side face83, thereby further preventing a reduction in the quality of the image displayed by optical device10c.

FIG.8is a schematic diagram of optical device10daccording to Embodiment 5. Specifically,FIG.8is an exploded perspective view of optical device10d.FIG.9is a schematic view illustrating examples of first face presser121din optical device10dinFIG.8.FIG.9illustrates the interior of body21dof housing20dviewed from a side where cover23lies.FIG.9illustrates three examples of first face presser121d. Note that the parts hatched with dash-dot-dot lines inFIG.9indicate portions in which optical element80is accommodated. Optical device10dmainly differs from optical device10in including housing20dinstead of housing20and fixing structure120dinstead of fixing structure120.

As illustrated inFIG.8, housing20dmainly differs from housing20in including body21dinstead of body21.

As illustrated inFIGS.8and9, fixing structure120dmainly differs from fixing structure120in including first face presser121dinstead of first face presser121, in not including side face presser122, and in including second face presser127d.

As illustrated inFIG.9, first face presser121dis provided for body21dof housing20dand presses the edge portion of optical element80from the side where first face81lies when optical element80is viewed from the side where first face81lies.

As illustrated in (a) inFIG.9, for example, first face presser121dincludes three edge pressers128dthat press the edge portion of first face81. That is, for example, first face presser121dis in contact with the edge portion of first face81at three different points to press the three points.

Moreover, as illustrated in (b) inFIG.9, for example, first face presser121dincludes four edge pressers128dthat press the edge portion of first face81. That is, for example, first face presser121dis in contact with the edge portion of first face81at four different points to press the four points.

Moreover, as illustrated in (c) inFIG.9, for example, first face presser121dpresses the edge portion of first face81around the entire circumference. That is, for example, first face presser121dis in contact with the entire edge portion of first face81to press the entire edge portion of first face81.

Note that, for example, first face presser121dmay include one, two, or more than four edge pressers128d.

As illustrated inFIG.8, second face presser127dpresses optical element80from the side where second face82lies. In this embodiment, second face presser127dpresses second face82. In this embodiment, second face presser127dis in contact with second face82. Note that, for example, second face presser127dmay not be in contact with second face82and may press second face82through other members. Second face presser127dincludes two second face pressing portions129dthat press second face82. That is, in this embodiment, second face presser127dis in contact with second face82at two different points to press the two points. Two second face pressing portions129dare disposed on cover23.

Note that, for example, second face presser127dmay include one or more than two second face pressing portions129d. Moreover, for example, second face presser127dmay have flexibility as does first side portion presser125(seeFIG.2).

Note that, in this embodiment, first side portion84and second side portion85of optical element80may be orthogonal to first face81and second face82and may be parallel to each other. This also applies to Embodiments 6 to 12.

In this embodiment, fixing structure120dfixes optical element80by holding optical element80with first face presser121dand second face presser127d.

Optical device10daccording to Embodiment 5 has been described above.

As described above, in optical device10daccording to Embodiment 5, optical element80includes side face83that links first face81and second face82, and fixing structure120dincludes first face presser121dprovided for housing20dand second face presser127d. When optical element80is viewed from the side where first face81lies, first face presser121dpresses the edge portion of optical element80from the side where first face81lies, whereas second face presser127dpresses optical element80from the side where second face82lies.

With this, optical element80can be held and fixed between first face presser121dand second face presser127d. Moreover, the edge portion of optical element80can be covered by first face presser121dwhen optical element80is viewed from the side where first face81lies. This prevents stray light, if any, coming from the edge portion from affecting the image displayed by optical device10d, thereby preventing a reduction in the quality of the image displayed by optical device10d.

Moreover, first face presser121dincludes three or more edge pressers128dthat press the edge portion of first face81.

This prevents displacement of optical element80, thereby further preventing a reduction in the quality of the image displayed by optical device10d.

Moreover, first face presser121dpresses the edge portion of first face81around the entire circumference.

This prevents displacement of optical element80, thereby further preventing a reduction in the quality of the image displayed by optical device10d. Moreover, even if stray light is produced at the edge portion of first face81, the stray light can be prevented from affecting the image displayed by optical device10d. This prevents a reduction in the quality of the image displayed by optical device10d.

This prevents damage to optical element80, thereby further preventing a reduction in the quality of the image displayed by optical device10d.

Moreover, housing20dincludes body21dthat accommodates optical element80and cover23that is attached to body21dto cover second face82of optical element80, and cover23is provided with second face presser127d.

With this, optical element80can be held from different sides to be fixed as cover23is attached to body21d. This easily prevents a reduction in the quality of the image displayed by optical device10d.

FIG.10is a schematic diagram of optical device10eaccording to Embodiment 6. Specifically,FIG.10is an exploded perspective view of optical device10e. Optical device10emainly differs from optical device10din including fixing structure120einstead of fixing structure120d.

As illustrated inFIG.10, fixing structure120emainly differs from fixing structure120din including second face presser127einstead of second face presser127d.

Second face presser127eis in surface contact with second face82to press second face82. That is, second face presser127ehas a shape along second face82and presses second face82while in surface contact with second face82. Note that, for example, second face presser127emay not be in contact with second face82and may press second face82through other members. Moreover, for example, second face presser127emay have flexibility as does first side portion presser125(seeFIG.2).

In this embodiment, fixing structure120efixes optical element80by holding optical element80with first face presser121dand second face presser127e.

Optical device10eaccording to Embodiment 6 has been described above.

As described above, in optical device10eaccording to Embodiment 6, fixing structure120eincludes second face presser127e, and second face presser127eis in surface contact with second face82to press second face82.

This prevents a pressing force from being concentrated on a part of second face82. Accordingly, optical element80can be held from different sides to be fixed while damage to second face82that reflects light is prevented. This further prevents a reduction in the quality of the image displayed by optical device10e.

FIG.11is a schematic diagram of optical element80fand the like according to Embodiment 7. (a) inFIG.11illustrates optical element80f, and (b) inFIG.11illustrates the interior of body21fof housing20fviewed from the side where cover23lies. The part hatched with dash-dot-dot lines in (b) inFIG.11indicates a portion in which optical element80fis accommodated. The optical device according to Embodiment 7 mainly differs from optical device10din including optical element80finstead of optical element80and housing20finstead of housing20d.

As illustrated in (a) inFIG.11, optical element80fmainly differs from optical element80in further including two protrusions89f. Two protrusions89fare disposed at the edge portion of first face81. Specifically, protrusions89fare disposed at edge portion86and edge portion87. In this embodiment, protrusions89fcorrespond to a first protrusion.

Note that, for example, optical element80fmay include one or more than two protrusions89f.

As illustrated in (b)FIG.11, housing20fmainly differs from housing20din including body21finstead of body21d. Body21fmainly differs from body21dillustrated in (b) inFIG.9in further including two recesses25f. Two recesses25fengage with respective protrusions89f. In this embodiment, recesses25fcorrespond to a second recess.

Note that, for example, housing20fmay include one or more than two recesses25f.

The optical device according to Embodiment 7 has been described above.

As described above, in the optical device according to Embodiment 7, optical element80fincludes protrusions89fdisposed at the edge portion of first face81, and housing20fincludes recesses25fengaging with protrusions89f.

With this, optical element80fcan be easily positioned relative to housing20f. This easily prevents a reduction in the quality of the image displayed by the optical device.

FIG.12is a schematic diagram of optical element80gand the like according to Embodiment 8. (a) inFIG.12illustrates optical element80g, and (b) inFIG.12illustrates the interior of body21gof housing20gviewed from the side where cover23lies. The part hatched with dash-dot-dot lines in (b) inFIG.12indicates a portion in which optical element80gis accommodated. The optical device according to Embodiment 8 mainly differs from the optical device according to Embodiment 7 in including optical element80ginstead of optical element80fand housing20ginstead of housing20f.

As illustrated in (a) inFIG.12, optical element80gmainly differs from optical element80fin further including two recesses90g. Two recesses90gare disposed at the edge portion of first face81. In this embodiment, recesses90gcorrespond to a first recess.

Note that, for example, optical element80gmay include one or more than two recesses90g.

As illustrated in (b) inFIG.12, housing20gmainly differs from housing20fin including body21ginstead of body21f. Body21gmainly differs from body21fin further including two protrusions26g. Two protrusions26gengage with respective recesses90g. In this embodiment, protrusions26gcorrespond to a second protrusion.

Note that, for example, housing20gmay include one or more than two protrusions26g.

The optical device according to Embodiment 8 has been described above.

As described above, in the optical device according to Embodiment 8, optical element80gincludes recesses90gdisposed at the edge portion of first face81, and housing20gincludes protrusions26gengaging with recesses90g.

With this, optical element80gcan be easily positioned relative to housing20g. This easily prevents a reduction in the quality of the image displayed by the optical device.

FIG.13is a schematic diagram of optical element80hand the like according to Embodiment 9. (a) inFIG.13illustrates optical element80h, and (b) inFIG.13illustrates the interior of body21hof housing20hviewed from the side where cover23lies. The part hatched with dash-dot-dot lines in (b) inFIG.13indicates a portion in which optical element80his accommodated. The optical device according to Embodiment 9 mainly differs from optical device10din including optical element80hinstead of optical element80and housing20hinstead of housing20d.

As illustrated in (a) inFIG.13, optical element80hmainly differs from optical element80in further including four recesses90h. Four recesses90hare disposed at the edge portion of first face81. In this embodiment, recesses90hcorrespond to the first recess.

Note that, for example, optical element80hmay include one, two, three, or more than four recesses90h.

As illustrated in (b) inFIG.13, housing20hmainly differs from housing20din including body21hinstead of body21d. Body21hmainly differs from body21dillustrated in (b) inFIG.9in further including four protrusions26h. Four protrusions26hengage with respective recesses90h. In this embodiment, protrusions26hcorrespond to the second protrusion.

Note that, for example, housing20hmay include one, two, three, or more than four protrusions26h.

The optical device according to Embodiment 9 has been described above.

As described above, in the optical device according to Embodiment 9, optical element80hincludes recesses90hdisposed at the edge portion of first face81, and housing20hincludes protrusions26hengaging with recesses90h.

With this, optical element80hcan be easily positioned relative to housing20h. This easily prevents a reduction in the quality of the image displayed by the optical device.

FIG.14is a schematic diagram of fixing structure120iand the like according to Embodiment 10. The optical device according to Embodiment 10 mainly differs from optical device10din including fixing structure120iinstead of fixing structure120d.

As illustrated inFIG.14, fixing structure120imainly differs from fixing structure120din further including side face presser122i. Side face presser122iincludes upper presser130i, lower presser131i, left presser132i, and right presser133i.

Upper presser130ipresses optical element80using an elastic force from above when optical element80is viewed from the side where first face81lies. Upper presser130iis disposed between the inner surface of body21dof housing20dand side face83of optical element80. For example, upper presser130iincludes a leaf spring.

Lower presser131ipresses optical element80from below when optical element80is viewed from the side where first face81lies. Lower presser131iis disposed between the inner surface of body21dof housing20dand side face83of optical element80.

Left presser132ipresses optical element80from the left when optical element80is viewed from the side where first face81lies. Left presser132iis disposed between the inner surface of body21dof housing20dand side face83of optical element80.

Right presser133ipresses optical element80using an elastic force from the right when optical element80is viewed from the side where first face81lies. Right presser133iis disposed between the inner surface of body21dof housing20dand side face83of optical element80. For example, right presser133iincludes a leaf spring.

Note that left presser132iand right presser133imay be interchanged. That is, a left presser may be provided to press optical element80using an elastic force from the left.

In this embodiment, fixing structure120ifixes optical element80by holding optical element80with first face presser121dillustrated inFIG.9, second face presser127dillustrated inFIG.8or second face presser127eillustrated inFIG.10, and side face presser122iillustrated inFIG.14. With this configuration, optical element80is pressed and fixed by the elastic forces in all directions including the up-down and left-right directions when viewed from the side where first face81lies inFIG.14and the depth direction (front-back direction) inFIG.14. Accordingly, the effect of the thermal expansion and vibration of optical element80in all directions on the image can be eliminated or minimized.

The optical device according to Embodiment 10 has been described above.

As described above, in the optical device according to Embodiment 10, fixing structure120iincludes side face presser122i, and side face presser122iincludes upper presser130ithat presses optical element80using the elastic force from above and right presser133ithat presses optical element80using the elastic force from the right when optical element80is viewed from the side where first face81lies.

This prevents damage to optical element80even if, for example, optical element80expands, thereby further preventing a reduction in the quality of the image displayed by the optical device.

FIG.15is a schematic diagram of fixing structure120jand the like according to Embodiment 11. The optical device according to Embodiment 11 mainly differs from the optical device according to Embodiment 10 in including fixing structure120jinstead of fixing structure120i.

As illustrated inFIG.15, fixing structure120jmainly differs from fixing structure120iin including side face presser122jinstead of side face presser122i. Side face presser122jmainly differs from side face presser122iin including left presser132jinstead of left presser132i.

Left presser132jpresses optical element80using an elastic force from the left when optical element80is viewed from the side where first face81lies. Left presser132jis disposed between the inner surface of body21dof housing20dand side face83of optical element80. For example, left presser132jincludes a leaf spring.

In this embodiment, fixing structure120jfixes optical element80by holding optical element80with first face presser121dillustrated inFIG.9, second face presser127dillustrated inFIG.8or second face presser127eillustrated inFIG.10, and side face presser122jillustrated inFIG.15. With this configuration, optical element80is pressed and fixed by the elastic forces in all directions including the up-down and left-right directions when viewed from the side where first face81lies inFIG.15and the depth direction (front-back direction) inFIG.15. Accordingly, the effect of the thermal expansion and vibration of optical element80in all directions on the image can be eliminated or minimized.

The optical device according to Embodiment 11 has been described above.

As described above, in the optical device according to Embodiment 11, fixing structure120jincludes side face presser122j, and side face presser122jincludes upper presser130ithat presses optical element80using the elastic force from above, left presser132jthat presses optical element80using the elastic force from the left, and right presser133ithat presses optical element80using the elastic force from the right when optical element80is viewed from the side where first face81lies.

This prevents damage to optical element80even if, for example, optical element80expands, thereby further preventing a reduction in the quality of the image displayed by the optical device.

FIG.16is a schematic diagram of fixing structure120kand the like according to Embodiment 12. The optical device according to Embodiment 12 mainly differs from the optical device according to Embodiment 7 in including fixing structure120kinstead of fixing structure120d.

Fixing structure120kmainly differs from fixing structure120din further including side face presser122k. Side face presser122kincludes upper presser130i, lower presser131i, upper left presser134k, and upper right presser135k.

Upper presser130iand lower presser131ihave already been explained in Embodiment 10, and thus detailed descriptions thereof will be omitted.

Upper left presser134kpresses optical element80fusing an elastic force from the upper left when optical element80fis viewed from the side where first face81lies. Upper left presser134kis disposed between the inner surface of body21dof housing20dand side face83of optical element80f. For example, upper left presser134kincludes a leaf spring.

Upper right presser135kpresses optical element80fusing an elastic force from the upper right when optical element80fis viewed from the side where first face81lies. Upper right presser135kis disposed between the inner surface of body21dof housing20dand side face83of optical element80f. For example, upper right presser135kincludes a leaf spring.

In this embodiment, fixing structure120kfixes optical element80fby holding optical element80fwith first face presser121dillustrated inFIG.9, second face presser127dillustrated inFIG.8or second face presser127eillustrated inFIG.10, and side face presser122killustrated inFIG.16. With this configuration, optical element80fis pressed and fixed by the elastic forces in all directions including the up-down and left-right directions when viewed from the side where first face81lies inFIG.16and the depth direction (front-back direction) inFIG.16. Accordingly, the effect of the thermal expansion and vibration of optical element80fin all directions on the image can be eliminated or minimized.

The optical device according to Embodiment 12 has been described above.

FIG.17is a schematic diagram of optical device10maccording to Embodiment 13. (a) inFIG.17illustrates optical element80m, housing20m, and fixing structure120min optical device10m. (b) and (c) inFIG.17illustrate optical element80min optical device10m. Note that housing20mis illustrated in cross section in (a) inFIG.17.

As illustrated inFIG.17, optical device10mincludes housing20m, optical element80m, and fixing structure120m. Note that, although not illustrated, optical device10mincludes a display that emits light representing an image to optical element80m, a light-transmitting cover that allows the light emitted from optical element80mto pass therethrough, and the like.

Housing20maccommodates optical element80mand the like. Housing20mincludes first member27mand second member28m. Note that, although not illustrated, housing20mincludes an emission portion that guides the light emitted from optical element80mto the outside of housing20m.

First member27mand second member28mare separable and detachable from each other in the up-down direction when optical element80mis viewed from a side where first face81mlies.

Optical element80mincludes first face81m, second face82mthat faces first face81m, and side face83mthat links first face81mand second face82m. Optical element80mis provided such that light is emitted from the display, enters optical element80mthrough first face81m, and then is reflected from second face82mto be guided to the outside of optical element80mthrough first face81m.

Side face presser122mincludes first side portion presser125mand second side portion presser126m.

First side portion presser125mconstitutes a part of first member27mand presses optical element80mfrom above when optical element80mis viewed from the side where first face81mlies.

Second side portion presser126mconstitutes a part of second member28mand presses optical element80mfrom below when optical element80mis viewed from the side where first face81mlies.

Note that, for example, when viewed from the side where first face81mlies, optical element80mmay be pressed in directions inclined with respect to the up-down direction as illustrated in (b) inFIG.17or in the up-down direction as illustrated in (c) inFIG.17.

In this embodiment, fixing structure120mfixes optical element80mby holding optical element80mfrom different sides with side face presser122m.

Optical device10maccording to Embodiment 13 has been described above.

FIG.18is a schematic diagram of optical device10naccording to Embodiment 14. Specifically,FIG.18is a cross-sectional view of optical device10n. InFIG.18, optical device10nis viewed from above.

As illustrated inFIG.18, optical device10nincludes housing20n, optical element80n, and fixing structure120n. Note that, although not illustrated, optical device10nincludes a display that emits light representing an image to optical element80nand a light-transmitting cover that allows the light emitted from optical element80nto pass therethrough.

Housing20naccommodates optical element80nand the like. Note that, although not illustrated, housing20nincludes an emission portion that guides the light emitted from optical element80nto the outside of housing20n.

Optical element80nincludes first face81n, second face82nthat faces first face81n, and side face83nthat links first face81nand second face82n. Optical element80nis provided such that light is emitted from the display, enters optical element80nthrough first face81n, and then is reflected from second face82nto be guided to the outside of optical element80nthrough first face81n.

First face81nis curved toward second face82n, and second face82nis curved away from first face81n.

First face presser121nis provided for housing20nand presses the edge portion of optical element80nfrom a side where first face81nlies when optical element80nis viewed from the side where first face81nlies. In this embodiment, first face presser121nincludes one edge presser145nand other edge presser146n.

One edge presser145npresses one edge portion91nof optical element80nfrom the side where first face81nlies when optical element80nis viewed from the side where first face81nlies. In this embodiment, one edge presser145nis in contact with edge portion91n. In this embodiment, edge portion91nis the left edge portion of optical element80nwhen optical element80nis viewed from the side where first face81nlies. In this embodiment, one edge presser145nis provided for housing20nand protrudes to the right from the inner surface of housing20nwhen optical element80nis viewed from the side where first face81nlies.

Other edge presser146npresses other edge portion92nof optical element80nfrom the side where first face81nlies when optical element80nis viewed from the side where first face81nlies. In this embodiment, other edge presser146nis in contact with edge portion92n. In this embodiment, edge portion92nis the right edge portion of optical element80nwhen optical element80nis viewed from the side where first face81nlies. In this embodiment, other edge presser146nis provided for housing20nand protrudes to the left from the inner surface of housing20nwhen optical element80nis viewed from the side where first face81nlies.

Second face presser127nincludes one edge presser147nand other edge presser148n.

One edge presser147npresses one edge portion93nof second face82nfrom a side where second face82nlies when optical element80nis viewed from the side where first face81nlies. In this embodiment, one edge presser147nis in contact with edge portion93n. In this embodiment, edge portion93nis the left edge portion of second face82nwhen optical element80nis viewed from the side where first face81nlies. In this embodiment, one edge presser147nis separate from housing20nand presses optical element80nby being pressed toward optical element80nby screw141n. Moreover, in this embodiment, one edge presser145nand one edge presser147nmutually hold optical element80nin directions A in which first face81nand second face82nface each other. That is, when viewed in direction A, one edge presser145nand one edge presser147noverlap each other.

Other edge presser148npresses other edge portion94nof second face82nfrom the side where second face82nlies when optical element80nis viewed from the side where first face81nlies. In this embodiment, other edge presser148nis in contact with edge portion94n. In this embodiment, edge portion94nis the right edge portion of second face82nwhen optical element80nis viewed from the side where first face81nlies. In this embodiment, other edge presser148nis separate from housing20nand presses optical element80nby being pressed toward optical element80nby screw144n. Moreover, in this embodiment, other edge presser146nand other edge presser148nmutually hold optical element80nin directions A in which first face81nand second face82nface each other. That is, when viewed in direction A, other edge presser146nand other edge presser148noverlap each other.

In this embodiment, fixing structure120nholds and fixes optical element80nbetween first face presser121nand second face presser127nas screw141nand screw144nare tightened.

Optical device10naccording to Embodiment 14 has been described above.

As described above, in optical device10naccording to Embodiment 14, fixing structure120nincludes second face presser127n, and first face presser121nand second face presser127nmutually hold optical element80nin directions A in which first face81nand second face82nface each other.

This prevents deformation of optical element80ncaused when optical element80nis held from different sides, thereby further preventing a reduction in the quality of the image displayed by optical device10n.

Moreover, fixing structure120nincludes second face presser127n, member140nwith screw hole139n, and screw141nthat presses second face presser127n(one edge presser147n) toward optical element80nwhile fitted in screw hole139n; and second face presser127n(one edge presser147n) presses optical element80nby being pressed toward optical element80nby screw141n.

This prevents displacement of optical element80n, thereby further preventing a reduction in the quality of the image displayed by optical device10n.

Note that this embodiment may be combined with any of fixing structures120iand120jof optical element80illustrated inFIGS.14and15, respectively, and fixing structure120kof optical element80fillustrated inFIG.16. In this case, optical element80nis pressed and fixed in all directions including the up-down and left-right directions when viewed from the side where first face81nlies inFIG.18and the depth direction (front-back direction, i.e., direction A inFIG.18). At this moment, for example, one edge presser147nand other edge presser148ncomposed of elastic members and fixing structure120i,120j, or120khaving elasticity can eliminate or minimize the effect of the thermal expansion and vibration of optical element80nin all directions on the image.

FIG.19is a schematic diagram of optical device10paccording to Embodiment 15. Specifically,FIG.19is a cross-sectional view of optical device10p. InFIG.19, optical device10pis viewed from above. Optical device10pmainly differs from optical device10nin including fixing structure120pinstead of fixing structure120n.

As illustrated inFIG.19, fixing structure120pmainly differs from fixing structure120nin including second face presser127pinstead of second face presser127n.

Second face presser127pmainly differs from second face presser127nin further including covering presser149p.

Covering presser149ppresses second face82nwhile covering second face82nbetween one edge presser147nand other edge presser148n. Covering presser149ppresses second face82nwhile in surface contact with second face82n. For example, covering presser149pis bonded to one edge presser147nand other edge presser148nwith adhesive or the like to be attached to one edge presser147nand other edge presser148n. Note that, for example, covering presser149pmay be integral to one edge presser147nand other edge presser148n.

In this embodiment, fixing structure120pholds and fixes optical element80nbetween first face presser121nand second face presser127pas screw141nand screw144nare tightened.

Optical device10paccording to Embodiment 15 has been described above.

As described above, in optical device10paccording to Embodiment 15, fixing structure120pincludes second face presser127p, and second face presser127pincludes one edge presser147nthat presses one edge portion93nof second face82n, other edge presser148nthat presses other edge portion94nof second face82n, and covering presser149pthat presses second face82nwhile covering second face82nbetween one edge presser147nand other edge presser148n.

This prevents displacement of optical element80n, thereby further preventing a reduction in the quality of the image displayed by optical device10p.

Note that this embodiment may be combined with any of fixing structures120iand120jof optical element80illustrated inFIGS.14and15, respectively, and fixing structure120kof optical element80fillustrated inFIG.16. In this case, optical element80nis pressed and fixed in all directions including the up-down and left-right directions when viewed from the side where first face81nlies inFIG.19and the depth direction (front-back direction, i.e., direction A inFIG.19). At this moment, for example, one edge presser147n, other edge presser148n, and covering presser149pcomposed of elastic members and fixing structure120i,120j, or120khaving elasticity can eliminate or minimize the effect of the thermal expansion and vibration of optical element80nin all directions on the image.

FIG.20is a schematic diagram of optical device10qaccording to Embodiment 16. Specifically,FIG.20is a cross-sectional view of optical device10q. InFIG.20, optical device10qis viewed from above. Optical device10qmainly differs from optical device10nin further including substrate200.

For example, substrate200is used to control optical device10q. Substrate200is held from different sides to be fixed between screw141nand member140nand between screw144nand member143nwhile screws141nand144nare respectively fitted in screw holes139nand142n.

Optical device10qaccording to Embodiment 16 has been described above.

As described above, optical device10qaccording to Embodiment 16 further includes substrate200held and fixed between screw141nand member140nwhile screw141nis fitted in screw hole139n.

This allows substrate200to be provided without an increase in the number of parts.

Note that this embodiment may be combined with any of fixing structures120iand120jof optical element80illustrated inFIGS.14and15, respectively, and fixing structure120kof optical element80fillustrated inFIG.16. In this case, optical element80nis pressed and fixed in all directions including the up-down and left-right directions when viewed from the side where first face81nlies in FIG. and the depth direction (front-back direction, i.e., direction A inFIG.20). At this moment, for example, one edge presser147nand other edge presser148ncomposed of elastic members and fixing structure120i,120j, or120khaving elasticity can eliminate or minimize the effect of the thermal expansion and vibration of optical element80nin all directions on the image.

FIG.21is a schematic diagram of optical device10raccording to Embodiment 17. Specifically,FIG.21is a cross-sectional view of optical device10r. InFIG.21, optical device10ris viewed from above. Optical device10rmainly differs from optical device10nin including optical element80rinstead of optical element80n.

Optical element80rmainly differs from optical element80nin including first face81rinstead of first face81nand side face83rinstead of side face83n.

In this embodiment, fixing structure120nholds and fixes optical element80rbetween first face presser121nand second face presser127nas screw141nand screw144nare tightened.

Optical device10raccording to Embodiment 17 has been described above.

Note that this embodiment may be combined with any of fixing structures120iand120jof optical element80illustrated inFIGS.14and15, respectively, and fixing structure120kof optical element80fillustrated inFIG.16. In this case, optical element80ris pressed and fixed in all directions including the up-down and left-right directions when viewed from a side where first face81rlies inFIG.21and the depth direction (front-back direction, i.e., direction A inFIG.21). At this moment, for example, one edge presser147nand other edge presser148ncomposed of elastic members and fixing structure120i,120j, or120khaving elasticity can eliminate or minimize the effect of the thermal expansion and vibration of optical element80rin all directions on the image.

FIG.22is a schematic diagram of optical device10saccording to Embodiment 18. Specifically,FIG.22is a cross-sectional view of optical device10s. InFIG.22, optical device10sis viewed from above. Optical device10smainly differs from optical device10nin including fixing structure120sinstead of fixing structure120n.

Fixing structure120smainly differs from fixing structure120nin including second face presser127sinstead of second face presser127n.

Second face presser127sincludes one edge presser147sand other edge presser148s.

One edge presser147smainly differs from one edge presser147nin being integral to housing20n. One edge presser147shas a thin, flat shape and has flexibility sufficient to pivot on housing20n.

Other edge presser148smainly differs from other edge presser148nin being integral to housing20n. Other edge presser148shas a thin, flat shape and has flexibility sufficient to pivot on housing20n.

In this embodiment, screws141nand144nare tightened from a state illustrated in (a) inFIG.22so that one edge presser147sand other edge presser148sare pressed toward optical element80nas illustrated in (b) inFIG.22. Thus, fixing structure120sfixes optical element80nby holding optical element80nwith first face presser121nand second face presser127s.

Optical device10saccording to Embodiment 18 has been described above.

As described above, in optical device10saccording to Embodiment 18, second face presser127sis integral to housing20n.

This prevents a reduction in the quality of the image displayed by optical device10swhile preventing an increase in the number of parts.

Note that this embodiment may be combined with any of fixing structures120iand120jof optical element80illustrated inFIGS.14and15, respectively, and fixing structure120kof optical element80fillustrated inFIG.16. In this case, optical element80nis pressed and fixed in all directions including the up-down and left-right directions when viewed from the side where first face81nlies inFIG.22and the depth direction (front-back direction, i.e., direction A inFIG.22). At this moment, for example, one edge presser147sand other edge presser148shaving flexibility and fixing structure120i,120j, or120khaving elasticity can eliminate or minimize the effect of the thermal expansion and vibration of optical element80nin all directions on the image.

FIG.23is a schematic diagram of optical element80taccording to Embodiment 19. (a) inFIG.23illustrates the cross-section of optical element80t, and (b) inFIG.23illustrates optical element80tviewed from a side where first face81tlies.

Optical element80tincludes first face81t, second face82tthat faces first face81t, and side face83tthat links first face81tand second face82t. Optical element80tis provided such that light is emitted from a display, enters optical element80tthrough first face81t, and then is reflected from second face82tto be guided to the outside of optical element80tthrough first face81t.

First face81tincludes curved portion97tand flat portion98t. Curved portion97tis curved toward second face82t. Flat portion98tis connected to the edge portion of curved portion97tand has a flat shape. Flat portion98tis orthogonal to direction B in which first face81tand second face82tface each other.

Second face82tincludes curved portion99tand flat portion100t. Curved portion99tis curved away from first face81t. Flat portion100tis connected to the edge portion of curved portion99tand has a flat shape. Flat portion100tis parallel to flat portion98t.

For example, the optical device according to this embodiment includes fixing structure120d(seeFIG.8), and fixing structure120dholds and fixes optical element80tby pressing flat portion98twith first face presser121dand by pressing flat portion100twith second face presser127d.

The optical device according to Embodiment 19 has been described above.

As described above, in the optical device according to Embodiment 19, first face81tincludes curved portion97tand flat portion98tconnected to the edge portion of curved portion97t, and first face presser121dpresses flat portion98t.

With this, even if first face81tincludes curved portion97t, optical element80tcan be held from different sides to be fixed when flat portion98tis pressed. This easily prevents a reduction in the quality of the image displayed by the optical device.

Note that, in addition to fixing structure120dinFIG.8, this embodiment may be combined with any of fixing structures120iand120jof optical element80illustrated inFIGS.14and15, respectively, and fixing structure120kof optical element80fillustrated inFIG.16. In this case, optical element80tis pressed and fixed in all directions including the up-down and left-right directions when viewed from the side where first face81tlies inFIG.23and the depth direction (front-back direction, i.e., direction B inFIG.23). At this moment, for example, second face presser127dhaving flexibility and fixing structure120i,120j, or120khaving elasticity can eliminate or minimize the effect of the thermal expansion and vibration of optical element80tin all directions on the image.

It should be noted that the “pressing” of the pressers in the above-described embodiments does not mean pushing movement only, but should be broadly interpreted, for example, as supporting, retaining, or abutting the faces of the optical element to be held from different sides.

Other Embodiments

Although an optical device according to one or more aspects of the present disclosure has been described based on embodiments, the present disclosure is not limited to the embodiments. Those skilled in the art will readily appreciate that embodiments arrived at by making various modifications to the above embodiments or embodiments arrived at by selectively combining elements disclosed in the above embodiments without materially departing from the scope of the present disclosure may be included within one or more aspects of the present disclosure.

Embodiment 1 described above is provided with reflective mirror60but is not necessarily limited to this configuration. For example, reflective mirror60may not be provided, and the light emitted from display40may directly enter optical element80. Moreover, for example, more than one reflective mirror may be provided, and the light emitted from display40may enter optical element80after being reflected multiple times. This also applies to Embodiments 2 to 19.

The above-described embodiments and the like disclose the following techniques.

An optical device includes:a display;an optical element that includes a first face and a second face facing the first face, the optical element receiving light from the display through the first face, reflecting the received light on the second face, and emitting the reflected light through the first face;a housing that accommodates the display and the optical element; anda fixing structure that fixes the optical element by holding the optical element from different sides of the optical element.

The optical device according to technique 1, whereinthe optical element includes a side face that links the first face and the second face, andthe fixing structure includes a first face presser provided for the housing and at least one of a second face presser or a side face presser, the first face presser pressing an edge portion of the optical element from a side where the first face lies when the optical element is viewed from the side where the first face lies, the second face presser pressing the optical element from a side where the second face lies, the side face presser pressing the optical element from a side where the side face lies.

The optical device according to technique 2, whereinthe side face includes a first side portion and a second side portion that faces the first side portion,the fixing structure includes the side face presser, andthe side face presser includes a first side portion presser that presses the optical element from a side where the first side portion lies and a second side portion presser that presses the optical element from a side where the second side portion lies.

The optical device according to technique 3, wherein the second side portion is inclined with respect to the first side portion to be away from the first side portion as the second side portion is closer to the first face than the second face, the first side portion presser presses the first side portion, and the second side portion presser presses the second side portion.

The optical device according to technique 4, whereinthe first side portion is an upper face portion of the optical element when the optical element is viewed from the side where the first face lies, andthe first side portion presser presses the first side portion from above the optical element when the optical element is viewed from the side where the first face lies.

The optical device according to technique 4, whereinthe first side portion is an upper face portion of the optical element when the optical element is viewed from the side where first face lies,the side face includes a third side portion and a fourth side portion, the third side portion being connected to a left end of the first side portion and located further leftward as the third side portion is closer to the second side portion when the optical element is viewed from the side where the first face lies, the fourth side portion being connected to a right end of the first side portion and located further rightward as the fourth side portion is closer to the second side portion when the optical element is viewed from the side where the first face lies, andthe side face presser includes at least one of a third side portion presser that presses the third side portion from above the optical element when the optical element is viewed from the side where the first face lies or a fourth side portion presser that presses the fourth side portion from above the optical element when the optical element is viewed from the side where the first face lies.

The optical device according to any one of techniques 2 to 6, whereinthe fixing structure includes the second face presser, andthe second face presser is in surface contact with the second face to press the second face.

The optical device according to any one of techniques 2 to 7, whereinthe first face presser includes three or more edge pressers each pressing an edge portion of the first face.

The optical device according to any one of techniques 2 to 7, whereinthe first face presser presses an edge portion of the first face around an entire circumference of the first face.

The optical device according to any one of techniques 2 to 9, whereinthe fixing structure includes the second face presser, andthe first face presser and the second face presser mutually hold the optical element in directions in which the first face and the second face face each other.

The optical device according to any one of techniques 2 to 10, whereinat least one of the second face presser or the side face presser has flexibility.

The optical device according to any one of techniques 2 to 11, whereinthe fixing structure includesthe second face presser,a member with a screw hole, anda screw that presses the second face presser toward the optical element while fitted in the screw hole, andthe second face presser presses the optical element by being pressed toward the optical element by the screw.

The optical device according to technique 12, whereinthe second face presser is integral to the housing.

The optical device according to technique 12 or 13, further includinga substrate held and fixed between the screw and the member while the screw is fitted in the screw hole may be provided.

The optical device according to any one of techniques 2 to 14, whereinthe fixing structure includes the second face presser, andthe second face presser includes one edge presser that presses one edge portion of the second face, an other edge presser that presses an other edge portion of the second face, and a covering presser that presses the second face while covering the second face between the one edge presser and the other edge presser.

The optical device according to any one of techniques 2 to 15, whereinthe optical element includes at least one of a first recess provided at an edge portion of the first face or a first protrusion provided at the edge portion of the first face, andthe housing includes at least one of a second protrusion that engages with the first recess or a second recess that engages with the first protrusion.

The optical device according to any one of techniques 2 to 16, whereinthe housing includesa body that accommodates the optical element anda cover that is attached to the body and covers the second face of the optical element, andat least one of the second face presser or the side face presser is provided for the cover.

The optical device according to any one of techniques 2, 10, 12, 15, and 17, whereinthe fixing structure includes the side face presser, andthe side face presser includes an upper presser and at least one of a left presser or a right presser, the upper presser pressing the optical element using an elastic force from above, the left presser pressing the optical element using an elastic force from a left, the right presser pressing the optical element using an elastic force from a right, when the optical element is viewed from the side where the first face lies.

The optical device according to any one of techniques 2 to 18, whereinthe first face includes a curved portion and a flat portion connected to an edge portion of the curved portion, andthe first face presser presses the flat portion.

The optical device according to any one of techniques 2 to 19, further including:a protecting member provided at at least one of a point between the first face and the first face presser, a point between the second face and the second face presser, or a point between the side face and the side face presser.

The optical device according to any one of techniques 2 to 20, further including:a light absorbing member provided at least in a part of the side face.

The optical device according to any one of techniques 1 to 21, further including:a metallic multilayer including a plurality of laminated metallic layers and disposed on the second face.

The disclosures of the following patent applications including specification, drawings, and claims are incorporated herein by reference in their entirety: Japanese Patent Application No. 2022-042245 filed on Mar. 17, 2022, and Japanese Patent Application No. 2022-135020 filed on Aug. 26, 2022.

INDUSTRIAL APPLICABILITY

The present disclosure is applicable to, for example, an optical device including an optical element that reflects light emitted from a display.