Flashing advisory sign

Claim 2

For use with a conventional advisory sign having a visible message, an optical shutter device for alternately blocking and transmitting the message, said device comprising: spacer means adapted to be attached to the sign in front of the message; electrically operable optical shutter means coupled to said spacer means for alternately blocking and transmitting light between the message and a viewing region in front of said device; and electrical power supply means coupled to said shutter means for sequentially controlling the state thereof.

Claim 3

The invention of Claim 1 wherein said spacer means includes a perimetral portion circumscribing the perimeter of the sign to shield the message from ambient light when said optical shutter means is in the light blocking state.

Claim 4

The invention of Claim 1 wherein said spacer means is provided with hanger means for removably attaching said optical shutter device to the sign.

Claim 5

The invention of Claim 1 wherein said optical shutter means includes a planar sheet of liquid crystal plastic-material.

Claim 6

The invention of Claim 4 wherein said optical shutter means further includes a pair of electrically conductive strips located along different edges of said sheet for enabling electrical connection with said power supply means.

Claim 7

The invention of Claim 4 wherein said spacer means includes a front flange portion and a rearwardly spaced mounting member, and wherein said sheet is received between said flange portion and said mounting member.

Claim 8

The invention of Claim 4 wherein said sheet is adhered to a transparent stiffener member.

Claim 9

The invention of Claim 4 wherein said sheet is laminated between a pair of transparent stiffener sheets.

Claim 10

The invention of Claim 1 wherein said optical shutter means includes a first planar sheet of liquid crystal material located in a first position of said spacer means, and a second planar sheet of liquid crystal material located in said spacer means rearwardly of said first planar sheet.

Claim 11

The invention of Claim 9 wherein each of said sheets is laminated between an associated pair of transparent stiffener sheets.

Claim 12

The invention of Claim 9 wherein said spacer means includes a front flange portion, a first rearwardly spaced mounting member, and a second mounting member located rearwardly of said first mounting member; and wherein said first sheet is received between said flange portion and said first mounting member and said second sheet is received between said first mounting member and said second mounting member.

Claim 13

For use with at least two advisory signs each having a visible member, an optical shutter device for controlling the visibility of the message from each sign, said device comprising: spacer means adapted to be attached to the sign in front of each message; optical shutter means carried by said spacer means for individually alternately blocking and transmitting light between each message and a viewing region in front of said spacer means; and electrical power supply means coupled to said shutter means for sequentially controlling the state thereof.

Claim 14

For use with at least two advisory signs each having a visible member, an optical shutter device for controlling the visibility of the message from each sign, said device comprising: spacer means adapted to be attached to the sign in front of each message; optical shutter means carried by said spacer means for individually alternately blocking and transmitting light between each message and a viewing region in front of said spacer means; and electrical power supply means coupled to said shutter means for sequentially controlling the state thereof.

Claim 15

The invention of Claim 12 wherein said optical shutter means includes a first planar sheet of liquid crystal plastic material positioned in front of the message of one of the signs, and a second planar sheet of liquid crystal plastic material positioned in front of the message of a different one of the signs.

Claim 16

The invention of Claim 13 wherein each of said sheets is laminated between an associated pair of transparent stiffener sheets.

Claim 17

The invention of Claim 13 wherein each of said first and second sheets includes a pair of electrically conductive strips located along different edges thereof for enabling electrical connection with said power supply means.

Claim 18

The invention of Claim 13 wherein said spacer means includes first and second outer front flange portions, a central front flange portion located between said first and second outer front flange portions, first and second rearwardly spaced outer mounting members respectively positioned adjacent said first and second outer front flange portions, and first and second rearwardly spaced central mounting members positioned adjacent said central front flange portion; and wherein said first sheet is received between said first outer front flange portion and said first outer mounting member at one edge portion thereof and between said central front flange portion and said first central mounting member at another edge portion thereof, and said second sheet is received between said second outer front flange portion and said second outer mounting member at one edge portion thereof and between said central front flange portion and said second central mounting member at another edge portion thereof.

Claim 19

The invention of Claim 13 wherein said first and second sheet are each adhered to a transparent stiffener member.

Claim 20

The invention of Claim 12 wherein said optical shutter means includes a first planar sheet located in a first position in said spacer means between the message of one of the signs and the front of the spacer means, a second planar sheet located in a second position in said spacer means between the message of another one of the signs and the front of the spacer means, a third planar sheet located in a third position in said spacer means between the first sheet and the associated message, and a fourth planar sheet located in a fourth position in said spacer means between the second sheet and the associated message, said first, second, third and fourth planar sheets being fabricated of liquid crystal plastic material.

Claim 21

The invention of Claim 18 wherein each of said sheets is laminated between an associated pair of transparent stiffener sheets.

Claim 22

The invention of Claim 18 wherein said first and third locations lie in a first plane and said second and fourth locations lie in a second plane.

Claim 23

The invention of Claim 15 wherein said spacer means includes first and second outer front flange portions, a central flange portion located between said first and second outer front flange portions, first and second rearwardly spaced outer mounting members respectively positioned adjacent said first and second outer front flange portions, first and second rearwardly spaced central mounting members positioned adjacent said central flange portion, first and second additional outer mounting members respectively positioned rearwardly of said first and second outer mounting members, and first and second additional central mounting members respectively positioned rearwardly of said first and second central mounting members; and wherein said first sheet is received between said first outer front flange portion and said first outer mounting member at one edge portion thereof and between said central front flange portion and said first central mounting member at another edge portion thereof; said second sheet is received between said second outer front flange portion and said second outer mounting member at one edge portion thereof and between said central front flange portion and said second central mounting member at another edge portion thereof; said third sheet is received between said first outer mounting member and said first additional outer mounting member at one edge portion thereof and between said first central mounting member and said first additional central mounting member at another edge portion thereof; and said fourth sheet is received between said second outer mounting member and said second additional outer mounting member at one edge portion thereof and between said second central mounting member and said second additional central mounting member at another edge portion thereof.

Claim 24

A marker device comprising: a marker element; an electrically operable optical shutter means for controlling the passage of light from said marker element to a viewing region; means for spacing said shutter means from said marker element; and electrical power supply means coupled to said shutter means for sequentially controlling the state thereof between a light blocking state in which the marker element is not visible in the viewing region and a light transmitting state in which said marker element is visible in the viewing region.

Claim 25

A marker device comprising: a marker element; an electrically operable optical shutter means for controlling the passage of light from said marker element to a viewing region; means for spacing said shutter means from said marker element; and electrical power supply means coupled to said shutter means for sequentially controlling the state thereof between a light blocking state in which the marker element is not visible in the viewing region and a light transmitting state in which said marker element is visible in the viewing region.

Claim 26

The invention of Claim 22 wherein said marker element comprises a flat strip of marker material.

Claim 27

The invention of Claim 23 wherein said optical shutter means comprises a sheet of liquid crystal plastic material.

Claim 28

The invention of Claim 22 wherein said optical shutter means comprises a sheet of liquid crystal plastic material.

Claim 29

The invention of Claim 25 wherein said optical shutter means further includes a pair of electrically conductive strips located along different edges of said sheet for enabling electrical connection with said power supply means.

Claim 30

The invention of Claim 22 wherein said spacing means comprises a housing having a bottom with an inner surface on which said marker element is received, said housing having upstanding side walls terminating in a top surface on which said shutter means is received.

Claim 31

The invention of Claim 27 further including a protective transparent top member received over said shutter means.

Claim 32

The invention of Claim 28 wherein said top member is glass.

Claim 33

The invention of Claim 28 wherein said top member is secured to said housing.

Claim 34

An advisory sign having a visible message, comprising: a retroreflective substrate bearing the message; and optical shutter means for blocking and transmitting light between said retroreflective substrate and a viewing area in front of the sign.

Claim 35

An advisory sign having a visible message, comprising: a retroreflective substrate bearing the message; and optical shutter means for blocking and transmitting light between said retroreflective substrate and a viewing area in front of the sign.

Claim 36

The sign of Claim 31 wherein said optical shutter means includes a liquid crystal means for at least one of scattering and absorbing light which in response to a prescribed input reduces the amount of such scattering or absorbing.

Claim 37

3 3 . The sign of Claim 32 further including electrode means for selectively applying an electric field across said liquid crystal means as said prescribed input.

Claim 38

34 . The sign of Claim 33 further including optically-transparent substrate means for supporting said electrode means.

Claim 39

3 5 . The sign of Claim 34 further including circuit means for energizing said electrode means to selectively apply said electric field.

Claim 40

An advisory sign having a visible message, comprising: a retroreflective substrate bearing the message; and optical shutter means directly coupled to said retroreflective substrate for blocking and transmitting light between said retroreflective substrate and a viewing area in front of the sign.

Claim 41

An advisory sign having a visible message, comprising: a retroreflective substrate bearing the message; and optical shutter means directly coupled to said retroreflective substrate for blocking and transmitting light between said retroreflective substrate and a viewing area in front of the sign.

Claim 42

The sign of Claim 36 wherein said optical shutter means includes a liquid crystal means for at least one of scattering and absorbing light and which in response to a prescribed input reduces the amount of such scattering or absorbing.

Claim 43

The sign of Claim 36 or 37 wherein said optical shutter means is laminated to said retroreflective substrate.

Claim 44

The sign of Claim 38 further including electrode means for selectively applying an electric field across said liquid crystal means as said prescribed input.

Claim 45

The sign of Claim 39 further including optically-transparent substrate means for supporting said electrode means.

Claim 46

The sign of Claim 40 further including circuit means for energizing said electrode means to selectively apply said electric field.

Claim 47

The sign of Claim 36 or 37 further including an optically-transparent, front protective cover coupled to said optical shutter means.

Claim 48

The sign of Claim 42 further including a back protective cover to which said retroreflective substrate is coupled.

Claim 49

The sign of Claim 36 or 37 wherein said retroreflective substrate includes a non-reflective portion forming a part of the message.

Claim 50

An advisory sign having a visible message, comprising: a message portion; a border about said message portion; and optical shutter means for alternately blocking and transmitting light between said border and a viewing area in front of the sign.

Claim 51

An advisory sign having a visible message, comprising: a message portion; a border about said message portion; and optical shutter means for alternately blocking and transmitting light between said border and a viewing area in front of the sign.

Claim 52

The sign of Claim 45 further including electrical power circuit means connected in circuit with said optical shutter means for sequentially controlling the state thereof.

Claim 53

The sign of Claim 45 wherein said border includes a retroreflective surface.

Claim 54

The sign of Claim 47 wherein said optical shutter means is directly coupled to said retroreflective surface.

Claim 55

The sign of Claim 48 wherein said optical shutter means is laminated to said retroreflective surface.

Claim 56

The sign of Claim 45 further including spacer means for spacing said border from said optical shutter means.

Claim 57

The sign of Claim 50 wherein said spacer means is provided with a hanger means for removably attaching said optical shutter means to the sign.

Claim 58

5 2 . The sign of Claims 45, 47, 48, 49, or 50 wherein said optical shutter means includes a liquid crystal means for at least one of scattering and absorbing light and which in response to a prescribed input reduces the amount of such scattering or absorbing.

Claim 59

The sign of Claim 52 further including circuit means for selectively applying an electric field across said liquid crystal material as said prescribed input to sequentially control the state thereof.

Claim 60

A message display comprising: a retroreflective substrate; and a patterned optical shutter means directly coupled to said retroreflective substrate for displaying the message by blocking and transmitting light between said retroreflective substrate and a viewing area in front of the sign.

Claim 61

A message display comprising: a retroreflective substrate; and a patterned optical shutter means directly coupled to said retroreflective substrate for displaying the message by blocking and transmitting light between said retroreflective substrate and a viewing area in front of the sign.

Claim 62

The sign of Claim 54 wherein said optical shutter means includes a liquid crystal means for at least one of scattering and absorbing light and which in response to a prescribed input reduces the amount of such scattering or absorbing.

Claim 63

The sign of Claim 54 wherein said patterned optical shutter means is laminated to said retroreflective substrate.

Claim 64

The sign of Claim 54 wherein said patterned optical shutter means includes optically-transparent electrode means for selectively applying an electric field, said electrode means patterned to form the message.

Claim 65

The sign of Claim 57 further including optically-transparent substrate means for supporting the electrode means.

Claim 66

The sign of Claim 58 further including circuit means for energizing said electrode means to selectively apply said electric field.

Claim 67

The sign of Claim 58 where said electrode means are patterned to form a dot matrix.

Claim 68

The sign of Claim 58 wherein said electrode means are patterned to form an unvarying message.

Claim 69

The sign of Claim 54 further including an optically-transparent front protective cover coupled to said patterned optical shutter means.

Claim 70

The sign of Claim 54 further including a back protective cover to which said retroreflective substrate is coupled.