JP2793574B2 - Display element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION This invention relates to display elements used alone as displays, but more generally used as pixels in an array of elements to form a changeable display sign. The invention proves to be particularly useful for signs and displays that must be viewed at a wide angle, such as bus destination signs.

[0002]

BACKGROUND OF THE INVENTION Display elements each use a rotor disk defining a median surface having opposing sides that conform and conform to the background, and a viewing cone (not necessarily a viewing cone) that surrounds the viewing direction. Not a rotating surface)
It is rotatable about an axis of rotation approximately parallel to the median plane to display the bright or dark side of the disk in the viewing direction considered to be the axis of the disk. The stator that forms the background for each disk is colored dark to accommodate the dark side of the disk, as opposed to the bright side of the disk. The bright and dark sides are displayed at the on and off positions, respectively.

A light emitting diode (L) corresponding to each disk
The ED) is positioned to form part of the pixels of the disk when the bright side (referred to as the on position) is displayed, and the LEDs illuminate the bright side of the disk when oriented to the on position. Is positioned and oriented. The LED is permanently on and must therefore be masked to the viewer in the off position of the disc.

The terms "forward" and "rearward" refer to the direction from the display element to the viewer and the opposite direction, respectively.

[0005] An "array" is an entire bus indicator or other indicator consisting of a "sub-array" composed of individual display elements or columns of individual elements.

[0006] Reference to "LED" herein is intended to include a group of LEDs.

[0007] "View direction" is the approximate center of the position (projected onto a plane perpendicular to the view direction) at which the display element or any array thereof is intended to be viewed.

[0008] A "view cone" encloses the view direction and includes the projection in the plane of the location where the display element or any array thereof is intended to be viewed.

In a preferred aspect of the invention, the angle at which the illuminated disk is viewed (in plan view) is approximately 150 symmetrically about the longitudinal axis of the bus on which the array is arranged.
°. However, the direct light from the LED is approximately 75 ° off the vertical axis on the side of the bus where the light from the LED is directed.
Observed in the arc. This is useful because bus signs are often viewed from the sidewalk. Thus, for buses used in most countries outside the UK and Australia, the 75 ° sector is on the right side of the bus centerline and in the UK and Australia on the left side.

It is known to use disks reinforced by the end of an optical fiber. For example, U.S. S. 4,974,353; with 04DEC90, No
rffolk U.S. S. 5,022,171; with 11JUN91, No
rfolk et al. S. 5,055,832; with 08JUN91, Br
See own. However, optical fibers are suitable for relatively narrow angle fields of view, but are not as well suited for wide angle fields of view, such as LEDs. Furthermore, LED
Are sufficiently inexpensive that LED display applications become practical when similar applications in fiber are impractical.

Another patent is an LED having a rotating disk.
It was used. See, for example, U.S. Patent 5,050,325, issued 24 SEP91. However, this patent
Neither does the disk itself mask the LEDs, nor does it provide a wide angle view. Thus, the LED had to be switched off in the off state. The design of this display element assumes that the LED is continuously on, while the disk switches between on and off positions,
This avoids the expense of a separate switching circuit for each LED.

Accordingly, it is an object of the present invention to provide a display element used alone or in an array of elements, wherein the appearance of the rotatable flip disk is enhanced in on-location by the LED. But
The LED must be masked by the disc to the observer in the off orientation, in which case the LED
Are directed to illuminate only the bright side of the associated disk and are viewed directly.

It is an object of the present invention to enable observation in a wide angle range in the on position, and in the off position,
Providing a display element or array thereof that masks light rays over a wide angle range, preferably wherein reflected light rays from the disk illuminated by the LEDs pass through sectors in the plan view that are symmetric with respect to the forward direction in the plan view. Is visible.

"Disc viewing direction" means a direction substantially perpendicular to the average attitude of the illuminated disc at the on and off positions and perpendicular to the axis of rotation. For reasons associated with the drive, the on and off disk orientations are slightly offset from each other to reduce the rotation to less than 180 ° where magnetic drives are used.
It is not parallel to the disks in the on and off positions. If an array of display elements is used, the viewing direction is taken as perpendicular to the plane approximating the seat of the array.

"Top view" means a view in a direction perpendicular to the viewing direction and parallel to the median plane of the array. Thus, the plan view for the bus is almost vertical, but in other applications it has real orientation.

As already mentioned, for the buses at the other vehicle destination signs, the plan view is almost horizontal,
It is then recognized that the viewing positions for directly viewing the LED light are all on one side of the light viewing direction for the illuminated disk.

In one aspect, the invention relates to an LED positioned to illuminate the bright side of a disk in an on position, with an on position (displaying a bright side to an observer) and an off position (displaying a bright side to an observer). Provide an appropriate display element for use as a pixel in an array having a disk that is movable between the display and the dark side, where the element or its array is a bus for viewing by pedestrians. (Or other vehicle) located in close proximity to the windshield. Proximity of the display element to the windshield is limited only by the movement of the disk between the on and off positions and the spacing required to allow for electrostatic charge interaction between the disk and the windshield.

The closer the array is to the windshield, the wider the viewing angle.

It is an object of the present invention that the light source used is, in contrast to alternative designs, very maintenance-free,
It is to provide a display element which is inexpensive.

It is an object of the present invention to provide a good definition in the sense of providing small pixels with respect to the size of the array and pixels having a relatively large effective area (for example, a large multi-pixel array (eg, 2 pixels).
(0:40 pixels) to provide display elements to form the appropriate pixels.

By "effective area" is meant the percentage of the marked area occupied by the bright area of the disk when all are on. This is a measure, if not strictly accurate, of the sign's effectiveness in view of the light effects of the LED and the effect of the preferred angle of the disk shine panel in the viewing direction. The need to make the effective surface as large as possible
The use of linear elements is preferred because it has the best "packing factor" and thus tends to provide the largest on-region in the display. Thus, the need to provide a small area of pixels with respect to the size of the array implies the use of square pixels.

"LED" refers to a chip mounted on a lens, but the chip and lens are often collectively referred to as an LED.

[0023]

SUMMARY OF THE INVENTION To this end, the invention provides, in one aspect, a stator wherein the stator is a front open housing, which is preferably generally rectangular in shape, and wherein the disk has a bright or dark side in the direction of view. Provide a display element or row or array thereof designed to rotate about an axis to display (When viewed in the viewing direction, the background to the disk is generally colored to conform to the dark disk side, as opposed to the bright disk side.) The LED associated with the stator has an And a side plate means for illuminating the bright side of the disc for the observer on each side. The means prevents leakage of the LED light in a direction transverse to the viewing direction.

The preferred drive for the disc is electromagnetic, according to techniques very well known to those skilled in the art. However, other drives are used within the scope of the invention.

In a preferred form of the invention, a printed circuit board ("PCB") is mounted on one side of the disk, and the LED illuminates the bright side of the disk when the latter is in the on position. Attach as follows. This depends on the attitude of the disk when it is on. Preferably, in the on position, the bright side of the disk is L
Slightly tilted toward the ED, and the LED beam is directed across the viewing direction. Means, preferably (L
The housing on the side of the LED lens and the PCB on the back (for the desired direction of the ED rays)
Prevents leakage of light rays that diverge very much from the direction of the D light rays.
If there is sufficient divergence of the LED beam from the disk lighting direction of the desired LED beam, the sidewalk observer in front of the bus (on one selected side) will be able to direct the light from the LED when the disk is in the ON position. I see.

The wall need not be a PCB within the scope of the invention. However, to prepare LED leads, PCB
It is considered most appropriate because it is convenient to prepare metal strips on the board.

Preferably, two for each element or row thereof
Only one side wall is provided, rather than one. then,
Opposing walls are provided by adjacent elements or rows in the LED emission direction.

[0028]

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, FIG. 1 shows a row of display elements according to the invention. The stator 10 of each element has a base 12, side walls 14S, to define a square display element that has good packing factors and uses the display area efficiently.
Figure 9 shows a front open housing having an end wall 14E upstanding from a base.

At the directly opposite corners of the element square, the tower 16
Has a vertical hole 18 for accommodating a spindle 20 of a display disk having a dark side surface 22D and a bright side surface 22B. The disk is notched at 31 and rotated past the adjacent core 26 as it moves between limit positions.

The drive is preferably magnetic, and the magnet 24 has an NS axis transverse to the axis of rotation of the disk, and a core 26B which is always of opposite polarity but is switched to rotate the disk. It is driven by switching of 26D. A permanent magnet 29 having its polar axis in the viewing direction V is mounted at the center of
6. Modify the magnetic field provided by 6 to provide a better starting torque. The drive is preferably a patent to MK Taylor, June 30, 1970, patent 3,518,66.
4, the contents of which are hereby incorporated by reference. The polarity of the core is determined by a power supply (not shown)
Is switched by

(Magnetic drive disks are typically 160 ° between the on and off limit positions due to the difficulty of full 180 ° rotation due to the lack of starting (magnetic) torque.
From <180 °. ) The magnet 24 is preferably constructed according to Winrow et al.
U.S. Patents 3,953,274 and 3,871,945
Built in the center layer of the layered disc according to the teachings of
This teaching is incorporated herein by reference. However, the magnet is mounted or mounted in other ways.

[0032] Different magnetic drives or non-magnetic drives may be used, all of which are within the scope of the invention.

On one side of each element, a side wall 30
It is provided in front of the walls 22E and 22S. As shown in FIG. 4, all the walls 30 of the row of individual elements 10
The elements 10 are combined in a single wall and the elements 10 are combined in a single molding. Wall 30 is preferably a PCB. On the wall facing the disk, LE
A D-chip (not shown) is mounted, and lens 32 is mounted in housing. The LEDs are mounted on the board 30 by an anode having a foil conductor 40 and cathodes 36,38. The housing 34 is LE
The beam from D is emitted in a small cone centered on the LED beam axis A transverse to the viewing direction and an aperture is provided to direct it to the disk. Disk (on position) is LED (by adjusting the length of core 26B)
3A, the end of which acts as a stop in the ON-only position of FIG. 3A, so that the luminous surface 22B of the disc is illuminated by the cone of the LED beam about the LED beam axis. . Light leakage in undesired directions is prevented in the lateral direction by the opaque wall of the housing 34 (having an open rear for the LED connections) and in the rear direction by the wall 30.

The LED beam axis direction is interdependent of the disk orientation in the on-orientation, so that changing the disk angle and its luminous side 22B is within the scope of the invention, but in such a case, The housing 34 is redirected such that the light beam at axis A illuminates the bright side 22B.

It is also noted that the light rays from the LED pass in front of the shining side of the disk (only in the ON position) and reach the observer directly. (The arc DIR in FIG. 7
(About 75 °). On the other hand, the disk illuminated surface illuminated by the LED has a symmetry arc I. of about 150 °. Seen around DISK.

The LED lens provides a range of viewing angle DIR of about 75 ° to the right side of the longitudinal axis of the bus (FIG. 9) in a manner very well known to those skilled in the art (FIG. 9). The viewing angle I.sub. It is designed to provide a range of DISK.

It is noted that the disc masks light leakage in the viewing direction or viewing cone to a sufficient extent in the off position. The end of the core 26D stops the disk at the off position. The PCB wall 30 prevents lateral leakage of light from the LED in both disk positions.

The wall is occupied on the other side of the element, but preferably has only one wall 30, so that light leakage will occur at the side 30 of the element-facing wall 30 at the wall 30 of the next adjacent element. It is avoided by the wall 30A (FIGS. 1 and 6) shown in some dotted form.

FIG. 4 shows a seven element sequence, where five of the elements are:
The bright side 22B is shown, and two of the elements
D is shown. FIG. 6 also shows the wall 3 of the next element in the array.
Indicates 0A.

FIG. 5 shows a bus carrying an array showing destinations. The schematic FIG. 7 does not indicate pixel-to-array size. In fact, the destination sign is, for example, 20 pixels high,
It is 40 pixels wide.

FIG. 6 shows how array A is approaching windshield C on bus B for observation by a pedestrian through the windshield. This "close proximity" is achieved due to the lighting provided inherent in the element by the LED.

The spacing between the array and its display elements on a bus or other vehicle sign is also shown in FIGS. 8A and 8C (prior art).
8B shows an array generated using the elements of the invention. In FIG. 8A, a prior art arrangement is shown. The bus BA has a windshield CA and a dot (or disk) matrix display AA located for viewing through the windshield CA. However, the display AA has a lamp or lamp group D on the disk shining side.
In order to be illuminated by A, it must be retracted from window CA. In FIG. 8B, the dot (or disk) array AB is as close to the windshield CB of the bus BB as the disk operation allows, with respect to disk operation and avoiding the electrostatic charge interaction between the disk and the windshield described below. Be placed. (Each invention disk has its own LED
Illuminated by ) It can be seen that the arrangement allowed by the inventive display element allows a much wider angular field of view of array AB in all directions than array AA. Yet another example of the prior art is shown in FIG. 8C, where the halogen lamps are located on the side or behind the display AA and are tilted and / or shaped to disperse the reflected light onto the array. The mirror EC is arranged to emit light. From the geometry, in the prior art device of FIG. 8C, the viewing angle is similar to that of the prior art device of FIG. 8A, which has a narrower viewing angle than the device of FIG. 8B.
It is easily recognized that it is substantially narrower than the device of FIG. 8B.

In addition, in both prior art devices of FIGS. 8A and 8C, the disks of the array are such that light rays are directed from the light source to the top (or "lamp remote" side) of the array rather than the bottom of the array.
It is noted that the illumination must be uneven because it must be transmitted to In contrast, in the inventive array of FIG. 8B, the illumination is more uniform because each disk is illuminated by a corresponding LED. The proximity of the array to the window is limited by two criteria.

First, in some cases, especially with plastics, non-conductive windshields tend to acquire a large electrostatic charge, and when approaching the disc, interact with static electricity generated in the insulating portion of the disc. Acts and interferes with disk movement. Thus, the disk seat must be sufficiently spaced from the windshield so that this does not occur.
By way of example only, a 0.5 "diameter disk is spaced 1" between the disk's axis of rotation and the windshield C (or CB) (see FIGS. 3A and 3B, which are not to scale). Second, there must be some spacing between the disk's swivel and the windshield so that the disk rotates (FIG. 3A).
And arc EA in FIG. 3B).

Thus, the phrase "immediate proximity" is subject to such first and second restrictions.

Thus, it is clear from the simple geometry that the improved (close) location of the array and its elements on the windshield will increase the possible viewing angles of the array.

The vertical array of FIG. 8B is contrasted with the slightly tilted array of FIG. 6, but in each variation there is an expanded possible viewing angle. This is in contrast to the large array draft shield spacing of prior art arrays that must be retracted from the draft shield to allow for the presence of lighting mounted on the bus to emit light backwards on the array.

In order for the inventive array to be placed close to the draft shield, it must often be curved in plan view to match the curved contour of the draft shield. Thus, the array preferably consists of a row that is only one element wide, as shown in FIG. 6, and a single element as needed to supplement the module.

FIG. 7 shows that approximately 1
Viewing angle of 50 ° Preferred range of DISK and LED
5 shows an asymmetric range of viewing angle DIR of about 75 ° for a direct view of FIG.

The asymmetry shown applies when the adjacent sidewalk is on the right side of the bus, as in most countries except the UK and Australia. British or Australian buses have an inverted "mirror image" of the element. In some cases, the depicted elements are simply inverted.

There is no restriction on the shape of the disc, but a square or rectangle makes more efficient use of space.

Although the axis of rotation of the disk is shown as diagonal, a vertical or horizontal axis may be used within the scope of the invention. Thus, the invention may be used, for example, on a disk having a vertical axis and the elongate shape may be Jo, March 25, 1986.
hn Brown, US Pat. No. 4,577,427, the contents of which are incorporated herein by reference.

The ends of the cores 26B and 26D are respectively
It acts as a stop for the disc in the on and off positions and determines the attitude of the disc in these positions, but the stop is provided in other ways and the core is
Used only for magnetic drives.

[Brief description of the drawings]

FIG. 1 is a partial view of a display element sequence according to the present invention.

FIG. 2 shows details of an LED, lens and housing assembly and LED housing and PCB according to the present invention.

FIG. 3 is a cross-sectional view taken along line 3A-3A of FIG. 1 showing a cross section of the disk at an on position displaying a bright side surface, and FIG. 1 is a cross-sectional view of the disk at an off position displaying a dark side surface.
FIG. 3B is a sectional view taken along line 3B-3B.

FIG. 4 is a front view of a display element row.

FIG. 5 is a schematic front view of a bus having a destination sign formed by an array according to the present invention.

FIG. 6 is a schematic cross-sectional view of the bus and sign portions taken in a vertical plane along the longitudinal axis of the bus.

FIG. 7 is a diagram directly showing a viewing angle with respect to an illumination dot and an LED.

FIG. 8 shows an arrangement of a prior art beacon array on a bus and an arrangement of an array of display elements of the invention for comparison with FIG. 8A, and shows an alternative to FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Stator 12 Base 14S Side wall 16 Tower 20 Support shaft 22B Light side 22D Dark side 24 Magnet 29 Permanent magnet

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G09F 13/32 G09F 9/33 G09F 9/37 302 G09F 11/04 G09F 13/20

Claims (14)

(57) [Claims] 1. A bright side surface (on position) in a viewing direction.
Or, a display element comprising a movable member movable to display a dark side surface (off position) and an associated LED positioned to illuminate the bright side surface when the member is in the on position. 2. The display element according to claim 1, wherein the member in an off position masks the LED in a viewing direction. 3. The display element according to claim 2, wherein the movable member is a disk having a rotation axis substantially transverse to a viewing direction. 4. The array of elements according to claim 2, wherein the arrays are arranged in rows, wherein a strip of the elements of a single element width forms part of the rows. 5. A vehicle destination sign comprising an array display element according to claim 4, located behind the vehicle windshield and visible through the windshield. 6. The element is arranged such that the array is designed to be located in close proximity to the windshield.
Vehicle destination sign described in. 7. The windshield, wherein the display element acquires an electrostatic charge and the element is sufficiently spaced from the windshield to avoid an interaction between the electrostatic charge on the windshield and the element. 5. The vehicle destination sign according to 5. 8. The windshield, as viewed vertically, wherein the array is curved and the array is formed from rows, whereby the array is curved to conform to the windshield. Vehicle destination sign. 9. A system comprising a stator and a rotator, wherein the rotator rotates an angle of about 160 ° to 180 ° between on and off limit positions about an axis substantially perpendicular to the viewing direction. A rotor mounted on the stator, the rotor displaying the bright and dark sides in the viewing direction at the on and off positions, respectively, and further, the rotation axis of the disk between the on and off positions. Means for producing rotation about the circumference, a wall mounted on at least one side of the stator protruding forward of the axis of rotation, and an LE mounted on the wall
D and the LED is in front of the disk, thus:
Means for limiting the rotation of the disk between an on position that illuminates the bright surface and an off position where the disk masks light from the LED in the viewing direction, wherein the wall defines the array. A display element for viewing in a viewing direction, characterized in that the display element is shaped to mask the light from the LED emitted transversely. 10. A system comprising a stator and a rotor, the rotor rotating about an axis between limit positions to display bright and dark sides at the ON and ON limit positions, respectively. A disk attached to the stator,
Means for effecting rotation about the axis of rotation of the disk between on and off positions, and to illuminate the bright side of the disk in the on position and to be covered by the disk in the off position A display for viewing along the field axis comprising an LED associated with the stator located and means associated with the stator for blocking light from the LED in a direction transverse to the field axis; element. 11. The display element according to claim 10, wherein said means for blocking light comprises a side wall mounted on said stator. 12. The display element according to claim 11, wherein the side wall is a PCB. 13. The display element of claim 12, wherein said LED is contained in an opaque enclosure to allow leakage of said light rays only in a direction illuminating said bright side. 14. The row of display elements according to claim 11, wherein the walls are combined to form a single wall on one side of the row.