Classifications

• • G—PHYSICS
  • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
  • G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
  • G09F19/00—Advertising or display means not otherwise provided for
  • G09F19/22—Advertising or display means on roads, walls or similar surfaces, e.g. illuminated
• • G—PHYSICS
  • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
  • G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
  • G09F19/00—Advertising or display means not otherwise provided for
  • G09F19/12—Advertising or display means not otherwise provided for using special optical effects
• • G—PHYSICS
  • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
  • G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
  • G09F19/00—Advertising or display means not otherwise provided for
  • G09F19/12—Advertising or display means not otherwise provided for using special optical effects
  • G09F19/20—Advertising or display means not otherwise provided for using special optical effects with colour-mixing effects

Definitions

• stroboscopic device More specifically, considerations of the vehicle's physical dimensions constrain a stroboscopic device's applicability.
• the design must take into account such information as the vehicle's height and width, its window size and spacing, and the positions of viewers within the vehicle. For example, close spacing of windows on a high speed train requires that stroboscopic discharges preferably be of high frequency and number in order that the display be visible to all occupants of a train.
• the dimensions of the environment such as the physical space available for hardware installation in the subway tunnel and the distances available over which to project images, impose further constraints on the size of elements of any device as well as on the quality and durability of its various parts.
• the board-to-board distance and the viewing distance total a backboard distance.
• the slitboard has a slitboard length along the trajectory and has a plurality of slits substantially perpendicular to the slitboard length. Each slit corresponds to a respective image of each series and has a slit width measured along the slitboard length and a slit center. Respective slit centers of adjacent slits are preferably separated by the frame-to-frame distance.
• FIG. 7 is a schematic plan view of second illustrative embodiment of the invention wherein the images are curved;
• FIG. 8 is a schematic plan view of a third illustrative embodiment of the invention wherein the images are inclined relative to the backboard;
• FIG. 29 is a schematic plan view of a preferred embodiment of a section of apparatus using baffles according to the present invention
• FIG. 30 is a schematic plan view of the apparatus of FIG. 23 using baffles according to the present invention
• a viewer preferably does not need to be in a vehicle.
• Complex stroboscopic illumination is preferably not needed.
• FIG. 3A An alternative geometry is shown in FIG. 3A, where track 31' is curved, and slitboard 22' and backboard 23 ' are correspondingly curved, so that all three are substantially "parallel" to one another.
• the other parameters are the same as in FIG. 3, except that, depending on the degree of curvature, there may be some adjustment in the amount of stretching or enlargement of the image as discussed below.
• One of the most significant departures of the present invention from previously known apparatus designed to be viewed from a moving vehicle is that no attempt is made to arrest the apparent motion of the image. That is, in the present device the image is always in motion relative to the viewer, and some part of the image is always viewable by the viewer.
• FIG. 4 the representation of movement of the viewer's eye is purely illustrative. In practice the viewer's gaze is fixed at a screen that is perceived to be stationary, and the entirety of the frame can be seen through peripheral vision, as with a conventional billboard.
• FIG. 5 illustrates the second persistence of vision effect. It shows viewer 30 looking in a fixed direction at three successive points in time.
• FIG. 6A a section of the true backboard 23 ' is shown between slitboard 22 and the projected backboard 23".
• a length PR of the backboard 23' defines a picture element 230'. This section 230' will appear to viewer 30 as if on projected flat backboard 23", as indicated.
• Viewer 30, at position A sees the left edge P of picture element 230' when slit 220 is at Q. Because the positions of picture element 230' and slit 220 are fixed relative to each other, they precisely determine the angle at which viewer 30 must look in order that slit 220 be aligned with an edge of the element 230'. Therefore, the right edge R of this picture element 230' will be visible when the device has moved relative to viewer 30 to a position where a line parallel to QR passes through A.
• second-order images can be used for graphic effect, if desired. Or, if not desired, they may be removed by increasing slitboard thickness D sb or the ratio D ff /Di, by introducing a light baffle 32 between slitboard 22 and backboard 23, or by altering the geometry of backboard 23. All of these techniques are described below. Still another possibly useful effect arises from the fact that the stretching effect distorts the proportions of image 230. One can remove this effect, if not desired, by preshrinking the images 230 so that the stretching effect restores the true proportions.
• V w the viewer's speed
• V w the viewer's speed
• D bs the backboard-to-slitboard distance
• D vs the distance from viewer to slitboard
• D t ' the perceived image width, should be no larger than the area visible to viewer 30 at a given instant -- for example, the width of a train window.
• this relation sets a maximum D ff . For example, for a train moving at about 30 miles per hour (about 48 kilometers per hour) , given a minimum frame rate of about 20 frames per second, the relation above determines that D ff can be as great as about 2 feet (about 67 cm) .
• D ⁇ D ff and one can view second order images, they will appear to abut the first order image, slightly out of synchronization. The resulting appearance will be like that of multiple television sets next to each other and starting their programs at slightly different times. This effect may be used for graphic intent, or, if not desired, three variations in parameters can remove it .
• slitboard thickness D sb so that second order images are obscured by the cutoff angle. That is, for any non-zero thickness of slitboard 22, there will be an angle through which if one looks one will not be able to see through the slits. As the thickness of slitboard 22 increases, this angle gets smaller, and can be seen to follow the relation
• backboard 71 bears curved images 730 so that second order images are not observed.
• the change in backboard shape will result in a slightly altered stretching effect.
• this stretching effect can be undone by preshrinking the image in the direction of motion.
• the embodiment illustrated in FIG. 7 has the potentially useful property not only of showing no second order images, but also of an arbitrarily wide first order image. This effect is related to, but distinct from, the stretching effect described above, which assumes a flat backboard geometry.
• the final observed width of the image is limited by the vignetting of the slitboard -- the exact relation can be found by solving Relation 5 for D ⁇ ' . It can be observed from FIG.
• each given slit 220 the leftmost sliver of the image is viewable when the viewer looks 90° to the left and the rightmost sliver is viewable when the viewer looks 90° to the right.
• the slivers in between are continuously viewable between these extreme angles.
• each image is observed as infinitely wide.
• the curved image 730 does not quite reach the slitboard 22, in order to illustrate the maximum viewing angle allowed by the vignetting of a non-zero width slitboard. In principle, the curve of image 730 may reach the slitboard.
• L dev i ce describes the luminance of the images on the backboard of the apparatus . Because the backboard is always viewed through the slitboard, which effectively filters the light passing through it, its brightness at the position of the viewer, B device is
• V w and all the distances except D ff are substantially constrained by the environment, and FR is constrained by properties of human visual perception. Therefore the relation defines an allowable range for D ff . It also puts a condition on the environments in which the present invention may be applied -- i.e., if the inequality does not hold between the far left and far right hand sides of the relation, the present invention will not be useful. Choosing a lower D ff puts second order frames closer to first order frames while improving the frame rate. Decreasing D ff also increases the transmission fraction without decreasing the resolution. Choosing a higher D ff moves the images farther apart at the expense of a reduced frame rate.
• this illumination preferably should not illuminate the exterior of the device, or illuminate the viewer's environment or reach the viewer directly, because greater contrast between the dark exterior and bright interior improves the appearance of the final image.
• This lighting requirement is less cumbersome than that for stroboscopic devices -- in a subway tunnel environment, this illumination need not be brighter than achievable with ordinary residential/ commercial type lighting, such as fluorescent tubes.
• the lighting preferably should be constant, so no timing complications arise.
• the interior of apparatus 10 should be physically sealed as well as possible from the exterior subway tunnel environment as discussed above, preferably while permitting dissipation of heat from the light source, if necessary.
• the enclosure may also be used to aid the illumination of the interior by reflecting light which would otherwise not be directed towards viewable images 230. Two examples show in more detail how the various parameters interrelate.
• FIG. 10 illustrates a technique of using one slitboard 101 as the backboard of a different slitboard 102, while simultaneously using that slitboard 102 as the backboard of the original slitboard 101.
• This configuration permits the back-to-back installation of two devices in the space of one.
• This apparatus 100 may be improved by offsetting one set of slits from the other by O ⁇ /2 , or some fraction of D ⁇ .
• FIG. 11 shows a simple schematic plan view of apparatus 100.
• FIG. 19 shows pedestrian 1901 walking in direction 1903 can see one animation when gazing at apparatus 2200 (shown in more detail in FIG. 22) along line of sight 1907, while pedestrian 1902 walking in the opposite direction 1904 can see a second animation when gazing at apparatus 2200 along line of sight 1908.

Landscapes

• Theoretical Computer Science (AREA)
• Accounting & Taxation (AREA)
• Marketing (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Business, Economics & Management (AREA)
• Two-Way Televisions, Distribution Of Moving Picture Or The Like (AREA)
• Illuminated Signs And Luminous Advertising (AREA)
• Closed-Circuit Television Systems (AREA)
• Controls And Circuits For Display Device (AREA)
• Ultra Sonic Daignosis Equipment (AREA)
• Endoscopes (AREA)

Priority Applications (9)

Applications Claiming Priority (2)

Publications (1)

Family

ID=22570228

Family Applications (1)

Country Status (13)

Cited By (4)

Families Citing this family (7)

Citations (3)

Family Cites Families (1)

• 2000
  • 2000-10-11 AU AU11991/01A patent/AU777922B2/en not_active Ceased
  • 2000-10-11 EP EP00973488A patent/EP1221156B1/de not_active Expired - Lifetime
  • 2000-10-11 AT AT00973488T patent/ATE257615T1/de not_active IP Right Cessation
  • 2000-10-11 JP JP2001530848A patent/JP2003511745A/ja not_active Withdrawn
  • 2000-10-11 CA CA002386898A patent/CA2386898C/en not_active Expired - Fee Related
  • 2000-10-11 CN CNB008156824A patent/CN1252669C/zh not_active Expired - Fee Related
  • 2000-10-11 MX MXPA02003730A patent/MXPA02003730A/es active IP Right Grant
  • 2000-10-11 BR BR0014736-2A patent/BR0014736A/pt not_active Application Discontinuation
  • 2000-10-11 WO PCT/US2000/028254 patent/WO2001027908A1/en active IP Right Grant
  • 2000-10-11 KR KR1020027004724A patent/KR100742168B1/ko not_active IP Right Cessation
  • 2000-10-11 DE DE60007649T patent/DE60007649T2/de not_active Expired - Fee Related
  • 2000-10-11 RU RU2002112328/09A patent/RU2248617C9/ru active
• 2002
  • 2002-11-29 HK HK02108726.2A patent/HK1049060B/zh not_active IP Right Cessation

Patent Citations (3)

Also Published As

Similar Documents

Legal Events