JP2018106000A - Image display device - Google Patents

Abstract

An object of the present invention is to achieve reduction in size and weight while enabling highly accurate diopter adjustment by simple operation. Kind Code: A1 An image display device has a display element holding section that holds a display element, an optical section that guides an image from the display element to the user's vision, and an operation section that has a dioptric adjustment knob. . The device includes: a supporting member for supporting the display element holding portion so as to make the distance between the operation portion and the display element holding portion variable and to press the display element holding portion toward the operation portion; and a diopter adjustment plate provided between the holding portion and rotatable according to the operation of the knob. The operating portion or the display element holding portion has at least three contact portions for contacting the visibility adjusting plate side. Furthermore, since the distance of the display element holding portion to the optical portion is varied within a preset target range, the regions of the diopter adjustment plate that contact the rotating contact portions have a thickness corresponding to the target range. [Selection diagram] Fig. 3

Description

  The present invention relates to an image display device typified by an HMD that can be mounted on the head.

  2. Description of the Related Art An HMD (Head Mounted Display) device that enlarges and displays an image displayed on an image display element such as a liquid crystal via a display optical system is well known. A mechanism is known in which the display diopter presented to the user is adjusted to a specific value by appropriately adjusting the distance between the image display element and the display optical system in this apparatus.

JP-A-8-152591 JP 2000-330069 A

  In Patent Document 1, the diopter can be adjusted by rotating the screw portion of the diopter adjustment dial to change the relative position of the LCD panel and the lens frame. However, the posture of the LCD panel cannot be maintained only by the screw portion. Therefore, it relies on a system in which a guide for maintaining the posture of the LCD panel is provided in the optical axis direction. In order to absorb the falling due to the fitting backlash, it is necessary to secure this fitting length, and a configuration extending in the optical axis direction is essential, which causes a problem in terms of downsizing the apparatus size.

  In Patent Document 2, diopter adjustment is realized by changing the position of the free-form surface prism, and the free-form surface prism can be moved in a plane perpendicular to the display surface of the display element. In order to restrict only movement in the optical axis direction, the flange side surfaces provided on both sides of the prism are configured to be fitted to the panel holder, but the fitting backlash cannot be completely removed. In addition, if the fixing screw is tightened after adjusting to a predetermined diopter, the prism rotates due to the tightening torque, and the relative positional relationship with the panel may be lost, and the target diopter may not be adjusted. In addition, in order to match the diopter desired by the user, there remains a problem in that it is necessary to loosen the screw each time the diopter is changed and to tighten the screw again when the diopter is adjusted to the desired diopter.

  The present invention has been made in view of the above problems, and it is an object of the present invention to provide a head-mounted image display device that can be reduced in size and weight while allowing display diopter adjustment by a simple operation.

In order to solve this problem, for example, an image display device of the present invention has the following configuration. That is,
A head-mounted image display device having a display element holding unit for holding a display element, an optical unit for guiding an image from the display element to the visual perception of an experienced person, and an operation unit having a diopter adjustment knob Because
A support member that supports a variable distance between the operation unit and the display element holding unit and presses the display element holding unit in a direction toward the operation unit;
A diopter adjustment plate that is provided between the operation unit and the display element holding unit and is rotatable according to the operation of the knob;
The operation part or the display element holding part has at least three contact parts for contacting the diopter adjustment plate side,
Since the distance between the display element holding part and the optical part is varied within a preset target range, the rotating region of the diopter adjusting plate that contacts the respective contact parts has a thickness corresponding to the target range. Have

  According to the present invention, it is possible to reduce the size and weight while enabling diopter adjustment with high accuracy by a simple operation.

The side view explaining the composition of a 1st embodiment. The center sectional view explaining composition of a 1st embodiment. The disassembled perspective view explaining the structure of 1st Embodiment. The figure which shows a display panel holder. The figure which shows a display prism holder. The figure explaining the diopter adjustment mechanism of 1st Embodiment. The figure which shows the diopter adjustment board of the example of 1st Embodiment. The figure which shows the diopter adjustment knob of 1st Embodiment. The figure which shows the connection of a display panel and a display panel holder. The figure which shows the path | route of the light beam guide | induced to a user's pupil from a display panel. The figure which shows the neutral point of a display diopter adjustment mechanism. The figure which shows a structure when a display diopter adjustment mechanism adjusts to the near distance side. The figure which shows a structure when a display diopter adjustment mechanism adjusts to the long distance side. The perspective view explaining the structure of 2nd Embodiment. The figure which shows the diopter adjustment board of 2nd Embodiment. The figure which shows the diopter adjustment knob of 2nd Embodiment. The figure explaining the diopter adjustment mechanism of 2nd Embodiment. The figure explaining the locking mechanism of 3rd Embodiment. The figure explaining the locked state of the locking mechanism of 3rd Embodiment.

  Embodiments according to the present invention will be described below in detail with reference to the accompanying drawings. Note that the image display device in the embodiment will be described as being mounted on an HMD that is a representative head-mounted display device. The diopter adjustment structure described below is for one of the left and right eyes in the HMD, and it should be understood that two structures for both eyes are actually provided. In addition, since the main feature of the embodiment is characterized by the structure related to the diopter adjustment, it is assumed that the circuit and control related to the display are well known, and the description thereof is omitted.

  The image display apparatus according to the present embodiment will be clarified from the following description. In brief, the apparatus displays a display element holding unit that holds a display element, and guides an image from the display element to the visual perception of the user. An optical unit and an operation unit having a diopter adjustment knob are accommodated. The apparatus includes a support member that supports the distance between the operation unit and the display element holding unit to be variable and presses the display element holding unit in a direction toward the operation unit, and the operation unit and the display element. A diopter adjusting plate provided between the holding portion and rotatable in accordance with the operation of the knob. The operation unit or the display element holding unit has at least three abutting portions for abutting on the diopter adjustment plate side. Further, since the distance of the display element holding unit from the optical unit is varied within a preset target range, the region of the diopter adjustment plate that contacts the contact unit by rotation has a thickness corresponding to the target range. It is what you have. The following are specific examples.

[First Embodiment]
FIG. 1 is a side view of an image display apparatus according to the first embodiment, FIG. 2 is a central sectional view, and FIG. 3 is an exploded perspective view.

  In the drawing, reference numeral 1 denotes a display prism as an optical unit, and reference numeral 2 denotes a display prism holder that holds the display prism 1. The display prism holder 2 is fastened to the display prism 1 with screws 11. Reference numeral 3 is a display panel, and reference numeral 4 is a display panel holder. The display panel 3 and the display panel holder 4 are bonded and fixed by a method described later. Reference numeral 10 denotes an image display apparatus main body.

  As shown in FIGS. 4A and 4B, recesses 4 a are provided at three locations on the surface of the display panel holder 4. The inner diameter of the recess 4 a is the same as the diameter of the ball bearing 5. Further, since a part of the ball bearing 5 protrudes (exposes), the depth of the concave portion 4a is dug deeper than the radius of the ball bearing 5 and shallower than the diameter. Furthermore, since the surface of the recess 4a is processed sufficiently smoothly, the ball bearing 5 can rotate with low friction inside the recess 4a. Protrusions 4 b are provided on opposite side surfaces of the display panel holder 4. The protrusion 4b is fitted in a groove 2a provided in the display prism holder 2 shown in FIG. The protrusion 4b is provided with a recess 4c, which is in contact with an end of a compression spring 6 to be described later.

  FIGS. 5A and 5B are perspective views of the display prism holder 2. A boss 2b is provided in the groove 2a, and one end of the compression spring 6 is fitted into the boss 2b so that the compression spring 6 cannot be removed.

  6A and 6B show a state in which the display panel holder 4 is assembled to the display prism holder 2. The recess 4c of the protrusion 4b of the display panel holder 4 is in contact with the other end of the compression spring 6 described above. Thereby, the display panel holder 4 is always urged in a direction away from the display prism 1 and in a pressure-contacting (pressing) direction to the display prism holder 2. Further, the display panel holder 4 is provided with a notch 4 d and is fitted to the boss 2 c of the display prism holder 2. Since the boss 2c and the groove 2a extend in a direction perpendicular to the display surface of the display panel 3, the display panel holder 4 and the display prism holder 2 are perpendicular to the display surface of the display panel 3. Can only move freely. Between the display panel holder 4 and the display prism holder 2, a circular ring-shaped rotatable diopter adjusting plate 7 is interposed.

  FIG. 7 shows the configuration of the diopter adjustment plate 7 in the present embodiment. On the surface of the diopter adjusting plate 7, three stepped contact portions 7 a having three thicknesses are provided. The three contact portions 7a are arranged at equal intervals in the circumferential direction, and are arranged at equal intervals of 120 degrees from the center of the circumference. The ball bearings 5 (three) abut against the abutting portions 7a (three) provided in a step shape of the diopter adjustment plate 7. The diopter adjusting plate 7, the ball bearing 5 and the display panel holder 4 are in pressure contact so that they are always in close contact with each other by the spring bias of the compression spring 6. The rear surface side of the diopter adjustment plate 7 is in close contact with the display prism holder 2 so that convex portions (not shown) are provided coaxially with the circumference so as to rotate with low friction. A circular hole 7b is formed at the center of the diopter adjusting plate 7, and a gear tooth 7c is formed on a part thereof. The angular range along the circumference where the gear teeth 7c are formed is substantially the same as the angular range along the circumference of the stepped contact portion 7a. The circumferential portion other than the gear teeth 7c is fitted to the flange portion 2d of the display prism holder 2 shown in FIG. 5, and is rotatable. The display prism holder 2 has a circular hole 2e, and a diopter adjustment knob 8 is fitted therein.

  FIG. 8 is a diagram showing the diopter adjustment knob 8. The diopter adjustment knob 8 includes an operation unit 8a that is pinched and rotated by a user at one end, and gear teeth 8b at the other end. The gear teeth 8 b mesh with the gear teeth 7 c of the diopter adjustment plate 7, and transmit rotational force to the diopter adjustment plate 7 when the diopter adjustment knob 8 is operated and rotated. On the surface of the operation section of the diopter adjustment knob 8, a notch groove 8 c is provided as a mark for allowing the user to visually recognize the angle at which the current knob rotates with a delay.

  As shown in FIG. 9, the display panel holder 4 is provided with an opening 4 e into which the outer portion of the cover glass portion 3 a that covers the display surface of the display panel 3 is fitted. The relative positional relationship between the display panel 3 and the display panel holder 4 is adjusted and bonded and fixed. That is, the horizontal and vertical lines on the display surface of the display panel 3 and the positions of the protrusions 4b and the notches 4d that serve as the position reference of the display panel holder 4 are adjusted with predetermined dimensions. The display surface of the display panel 3 has matrix-like light emitters aligned. When an image signal is received by the substrate on the back surface of the display panel 3, the light emission signal is passed to each light emitter after performing spatial modulation processing, and a display image is displayed. As shown in FIG.

FIG. 10 is a diagram schematically showing a display optical system composed of the display panel 3 and the display prism 1, and a path until a light beam emitted from the display panel 3 reaches the user is indicated by a two-dot chain line. Yes. Light rays emitted from the display surface of the display panel 3 enter the free curved surface C surface 1 c of the display prism 1. Thereafter, the light is refracted on the C surface 1c and the optical path is bent, and then reaches the free curved surface A surface 1a. Since the incident angle between the A surface 1a and the light beam is deep, the light beam is totally reflected on the A surface 1a. Then, the reflected light from the A surface 1a reaches the free curved surface B surface 1b. Since the incident angle between the B surface 1b and the light beam is shallow, the light beam is not totally reflected. However, an aluminum foil film is deposited on the surface of the free curved surface B surface 1b. For this reason, the light ray is reflected at the reflectance of 80% or more on the B surface 1b. The reflected light beam proceeds to the free curved surface A surface 1a as it is, and is emitted from the A surface 1a. After exiting, the exit pupil 1d is formed at a point approximately 20 mm away from the free curved surface A surface 1a. The image displayed on the display panel 3 is enlarged and displayed through the display prism 1, and the user can observe a wide-angle video. At this time, the image on the display panel 3 can be observed best when the pupil in the user's eyeball and the position of the exit pupil 1d coincide. In this embodiment, the position of the exit pupil 1d is set to a position 20 mm from the A plane 1a. However, the present invention is not limited to this, and it is desirable to design the distance so as not to cause a problem in actual use in consideration of the use of glasses or the like.

Next, a case where the user rotates the diopter adjustment knob 8 in the CW direction (clockwise direction) to change to the short distance diopter will be described. FIGS. 11A to 11C are views showing the positional relationship between the diopter adjustment knob 8, the display prism holder 2, and the diopter adjustment plate 7 in the initial state. In order to observe the object near the user from this initial state, the diopter adjustment knob 8 is rotated in the CW direction and the operation knob is moved to the “NEAR” side when changing to the near distance diopter. Align the notch. A state in which the diopter adjustment knob 8 is rotated in the CW direction is shown in FIGS. When the diopter adjustment knob 8 is rotated in the CW direction, the rotational force is transmitted to the diopter adjustment plate 7 via the gear teeth 8b at the rotation shaft end of the diopter adjustment knob 8, and the diopter adjustment plate 7 is also rotated in the CW direction. To do. As described above, the display panel holder 4 can move only in the vertical direction with respect to the display prism holder 2. For this reason, when the diopter adjustment plate 7 rotates, the ball bearing 5 in contact with the diopter adjustment plate 7 is relatively displaced, and the three stepped contact provided on the diopter adjustment plate 7 Of the contact portions 7a, the step comes into contact with the highest surface. That is, the diopter adjustment plate 7 and the display panel 3 move away from each other. As a result, the air space between the display panel 3 and the display prism 1 is narrowed, and the diopter is adjusted to the near distance side.

  Next, a case where the user rotates the diopter adjustment knob 8 in the CCW direction (counterclockwise direction) to change to the long distance diopter will be described.

  When the user changes and adjusts to the long-distance diopter for observing an object far away, the diopter adjustment knob 8 is rotated in the CCW direction, and the notch of the operation knob is placed on the “FAR” side. Match. FIGS. 13A to 13C show a state in which the diopter adjustment knob 8 is rotated in the CCW direction. When the diopter adjustment knob 8 rotates, the diopter adjustment plate 7 rotates. At this time, the relative position between the position of the staircase provided on the diopter adjustment plate 7 and the part holding the ball bearing 5 that determines the position of the diopter direction of the display panel holder 4 is changed according to the rotation phase. A position that is one step lower than the state is selected. That is, the diopter adjustment plate 7 and the display panel 3 move in a narrowing direction. As a result, the air space between the display panel 3 and the display prism 1 is widened, and the diopter is adjusted to the far side.

  As understood from the above description, when the user rotates the diopter adjustment knob 8 in the embodiment, the display panel 3 can change its position relative to the display prism 1 along the arrow 100 in FIG. Become. In addition, the display panel holder 4 is in pressure contact at three equally spaced positions on the diopter adjustment plate 7 by the action of the compression spring 6. Therefore, the occurrence of rattling in the above relative movement can be suppressed, and the structure related to the relative movement can be made compact.

  In the present embodiment, the diopter adjustment mechanism has been described with three stages of the initial position (center position), “NEAR”, and “FAR”. However, the number of stages to be adjusted is not limited to three, and a plurality of stages of two or more stages are adjusted. It is sufficient to have the adjustment point.

  In the above embodiment, the recess 4a is described as being provided in the display panel holder 4, but it may be provided on the display prism holder 2 side. In short, as the diopter adjusting plate 7 rotates, the distance between the display prism holder 2 and the display panel holder 4 only needs to change according to the change in thickness.

  In the embodiment, the number of the recesses 4a is three, but may be four or more. However, the plane can be defined by three points. When manufacturing errors are taken into account, it is desirable to use three.

[Second Embodiment]
FIGS. 14A and 14B are perspective views illustrating a configuration of a main part corresponding to one eye of the HMD to which the embodiment is applied. The second embodiment has substantially the same configuration as the first embodiment. Therefore, the same reference numerals are assigned to the same functional components as those in the first embodiment.

  FIG. 15 is a perspective view of the diopter adjustment plate 7 in the second embodiment. As shown in the figure, the three contact portions 7a provided on the diopter adjustment plate 7 in the second embodiment are equally spaced 120 degrees from the center of the diopter adjustment plate 7 as in the first embodiment. The shape represented by the thickness viewed from the side surface is a tapered shape (a structure in which the thickness changes steplessly). The ball bearing 5 comes into contact with the tapered contact portion 7 a of the diopter adjustment plate 7. The diopter adjusting plate 7, the ball bearing 5 and the display panel holder 4 are always in close contact with each other by the biasing force of the compression spring 6. The rear surface side of the diopter adjustment plate 7 is in close contact with the display prism holder 2 so that a convex portion is provided coaxially with the circumference so as to rotate with low friction. A circular hole 7b is opened at the center of the diopter adjustment plate 7, and a gear tooth 7c is formed in a part of the hole. The range in which the gear teeth 7c are formed is substantially the same angle as the tapered contact portion 7a. The circumferential portion other than the gear teeth 7c is fitted to the flange portion 2d of the display prism holder 2 shown in FIG. 5, and is rotatable. Further, the display prism holder 2 has a circular hole 2e (see FIG. 5), and a diopter adjustment knob 8 is fitted therein.

  FIGS. 16A to 16C show the structure of the diopter adjustment knob 8 in the second embodiment, and FIG. 17 shows the diopter adjustment mechanism of the second embodiment.

  The diopter adjustment knob 8 in the second embodiment is provided with a lock portion 8e. The lock portion 8e is intentionally enlarged in diameter so that a frictional force acts on the circular hole portion 2e of the display prism holder 2 in a natural state. By pushing the lock release portion 8d, the lock portion 8e is bent in the central axis direction, and the frictional force with the circular hole 2e of the display prism holder 2 can be released. That is, unless the lock release portion 8d is pushed, the circular hole 2e of the display prism holder 2 and the lock portion 8e are subjected to frictional force, and the rotational position of the diopter adjustment knob 8 can be kept fixed.

  With the above configuration, a case will be described in which the user rotates in the CW direction while pressing the lock release portion 8d of the diopter adjustment knob 8 to change to the short distance diopter. When the user adjusts to near-distance diopter for observing an object near the hand, the diopter adjustment knob 8 is rotated in the CW direction, and the operation knob is operated to the “NEAR” side. At this time, the portion of the diopter adjusting plate 7 that contacts the tapered contact portion 7a and the ball bearing 5 changes according to the rotation angle of the diopter adjusting knob 8, and the distance between the display prism 1 and the display panel 3 gradually changes. Approaches. For this reason, the display diopter becomes closer to the short distance side according to the rotation of the diopter adjustment knob 8, and an arbitrary display diopter desired by the user can be selected. After the desired display diopter is selected, the lock release portion 8d of the diopter adjustment knob 8 is released, so that the lock portion 8e and the hole portion 2e of the display prism holder 2 come into contact with each other, and a frictional force acts. As a result, rotation of the diopter adjustment knob 8 is restricted, and the diopter adjustment knob 8 can be fixed to a desired display diopter.

  Next, a case where the user rotates in the CCW direction while pressing the lock release portion 8d of the diopter adjustment knob 8 to change to the long distance diopter will be described. When the user adjusts to the long-distance diopter for observing the object near the hand, the diopter adjustment knob 8 is rotated in the CCW direction, and the operation knob is operated to the “FAR” side. At this time, the portion of the diopter adjusting plate 7 that contacts the tapered contact portion 7a and the ball bearing 5 changes according to the rotation angle of the diopter adjusting knob 8, and the distance between the display prism 1 and the display panel 3 gradually changes. Leave. For this reason, the display diopter becomes a long distance side according to the rotation of the diopter adjustment knob 8, and an arbitrary display diopter desired by the user can be selected. After the desired display diopter is selected, the lock release portion 8d of the diopter adjustment knob 8 is released, so that the lock portion 8e and the hole portion 2e of the display prism holder 2 come into contact with each other, and a frictional force acts. As a result, rotation of the diopter adjustment knob 8 is restricted, and the diopter adjustment knob 8 can be fixed to a desired display diopter.

  As can be seen from the above description, according to the second embodiment, in addition to the operational effects shown in the first embodiment, the diopter can be adjusted steplessly and the position can be locked. It becomes.

[Third Embodiment]
18 (a) and 18 (b) are diagrams illustrating the third embodiment, in which the configuration related to the lock portion shown in the second embodiment is configured as a separate part. Therefore, the same functional parts as those in the second embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  Reference numeral 9 in FIGS. 18A and 18B is a panel lock portion for regulating and fixing the diopter with a display panel lock lever that restricts the movement of the display panel and fixes the position.

  The display panel lock lever 9 is provided with a rotation center hole 9a and a cam groove 9b, which are fitted to two shafts 2f and 2g extending from the side surface of the display prism holder 2, respectively. The states shown in FIGS. 18A and 18B are unlocked states. The cam groove 9b provided in the display panel lock lever 9 is formed so as to gradually shorten the distance between the two shafts 2f and 2g, and when the user performs an operation of tilting the display panel lock lever 9, FIG. 19, the effect | action which narrows the space of the groove part 2a in which the protrusion 4b which guides the display panel holder 4 fits acts. Therefore, the projection 4b of the display panel holder 4 is sandwiched between the groove portions 2a that are guided and guided, and the display panel holder 4 cannot move.

  With the above configuration, a case where the user releases the display panel lock lever 9 of the diopter adjustment knob 8 and rotates it in the CW direction to change to the short distance diopter will be described. When the user adjusts to near-distance diopter for observing an object near the hand, the diopter adjustment knob 8 is rotated in the CW direction, and the operation knob is operated to the “NEAR” side. At this time, the portion of the diopter adjusting plate 7 that contacts the tapered contact portion 7a and the ball bearing 5 changes according to the rotation angle of the diopter adjusting knob 8, and the distance between the display prism 1 and the display panel 3 gradually changes. Approaches. For this reason, the display diopter becomes closer to the short distance side according to the rotation of the diopter adjustment knob 8, and an arbitrary display diopter desired by the user can be selected. After selecting a desired display diopter, the display panel lock lever 9 is operated to fix the position of the display panel holder 4 so that the display diopter can be fixed to a desired display diopter.

  Also in the third embodiment described above, the same operational effects as those of the second embodiment described above can be obtained.

DESCRIPTION OF SYMBOLS 1 ... Display prism, 2 ... Display prism holder, 3 ... Display panel, 4 ... Display panel holder, 5 ... Ball bearing, 6 ... Compression spring, 7 ... Diopter adjustment plate, 8 ... Diopter adjustment knob, 9 ... Lock lever 10 ... HMD, 11 ... Bis

Claims (7)

A head-mounted image display device having a display element holding unit for holding a display element, an optical unit for guiding an image from the display element to the visual perception of an experienced person, and an operation unit having a diopter adjustment knob Because
A support member that supports a variable distance between the operation unit and the display element holding unit and presses the display element holding unit in a direction toward the operation unit;
A diopter adjustment plate that is provided between the operation unit and the display element holding unit and is rotatable according to the operation of the knob;
The operation part or the display element holding part has at least three contact parts for contacting the diopter adjustment plate side,
Since the distance between the display element holding part and the optical part is varied within a preset target range, the rotating region of the diopter adjusting plate that contacts the respective contact parts has a thickness corresponding to the target range. An image display device comprising:   The image display apparatus according to claim 1, wherein the optical unit is a prism that magnifies an image from the display element.   The image display device according to claim 1, wherein the target range is expressed by two or more stages.   The image display device according to claim 1, wherein the target range is expressed in a stepless manner.   The image display apparatus according to claim 4, further comprising a member that is provided on the knob and fixes a rotational position of the knob.   The image display apparatus according to claim 4, further comprising a member for fixing a distance between the operation unit and the display element holding unit. The contact portion is
Ball bearings,
7. The image display device according to claim 1, further comprising: a concave portion that rotatably accommodates the ball bearing and exposes a part of the ball bearing. 8.

Images