Two window indicator

A multi-ply radiation dosage indicator comprising:

• a first ply having at least a first visible indicia, a second visible indicia, a third visible indicia, and a fourth visible indicia, wherein the first visible indicia is positioned adjacent to the third visible indicia and the second visible indicia is position adjacent to the fourth visible indicia on the first ply;
• a second ply having at least a first radiation sensitive zone and a second radiation sensitive zone, wherein the first radiation zone is configured to overlay the first visible indicia and the second radiation zone is configured to overlay the second visible indicia;
• wherein each radiation sensitive zone is configured to change opacity in response to exposure to a certain radiation dosage exceeding an independently predetermined threshold of each radiation sensitive zone;
• and wherein the first and second visible indicia coupled with the third and fourth visible and the second indicia, respectively, together providing a visual indication as to whether said the indicator has been exposed to a certain radiation dosage exceeding one or more the predetermined thresholds.

A multi-ply radiation dosage indicator comprising:

• a first ply having at least a first and a second visible indicia thereon;
• a second ply having at least a first radiation sensitive zone and a second radiation sensitive zone, wherein the first radiation sensitive zone is configured to overlay the first visible indicia and the second radiation sensitive zone is configured to overlay the second visible indicia;
• wherein the first radiation sensitive zone and the second radiation sensitive zone comprise a polyacetylene compound having the capability to change opacity in response to exposure to a certain radiation dosage that exceeds an independently predetermined threshold of each radiation sensitive zone to make the first visible indicia, the second visible indicia, or both the first and second visible indicia of the first ply nonvisible;
• a third ply overlying the second ply, the third ply including at least a first and second viewing zones, through which the first and second visible indicia of said first ply may be exposed to view, the third ply further includes a first and second visible indicia thereon positioned adjacent to the first and second viewing zones, respectively, the first and second visible indicia of said first ply and the first and second visible indicia of said third ply together providing a visual indication as to whether the indicator has been exposed to a certain radiation dosage exceeding the predetermined threshold(s);
• and
• a fourth ply constituting at least a first and second optical filters configured to overlay the first and second radiation sensitive zones, respectively;
• wherein the indicator is configured to be removably or permanently attachable to a substrate, and wherein the first and third plies are opaque and have border portions extending beyond the second and fourth plies, the border portion of the first ply being attached to the border portion of the third ply, sealing the edges of the second and fourth plies from exposure to ambient light.

A multi-ply radiation dosage indicator comprising:

• a first ply having a first visible readable indicia, a second visible readable indicia, a third visible readable indicia, and a fourth visible readable indicia thereon, the first visible readable indicia positioned adjacent to the third visible readable indicia and the second visible readable indicia position adjacent to the fourth visible readable indicia;
• a second ply having at least a first radiation sensitive zone and a second radiation sensitive zone configured to overlay the first and the second visible readable indicia, respectively;
• wherein the second ply is configured to be transparent and the first and second radiation sensitive zone(s) are configured to become sufficiently opaque in response to exposure to a certain radiation dosage that exceeds a predetermined threshold, making the first and second visible readable indicia nonvisible and providing a visual readable indication that the indicator has been exposed to the certain radiation dosage exceeding the predetermined threshold;
• at least two optical filters overlying said second ply;
• a third ply overlying the optical filters and having at least one zone through which the first visible readable indicia and the second visible readable indicia of the first ply are configured to be exposed to view;
• wherein the indicator is configured to be removably or permanently attachable to a substrate;
• and
• wherein the first and third plies are opaque and further comprise border portions extending beyond the second and fourth plies, the border portion of the first ply being attached to the border portion of the third ply so as to seal the edges of the second and fourth plies from exposure to ambient light.

A method for making a multi-ply radiation dosage indicator comprising:

• providing a first ply having at least a first and second visible indicia thereon;
• providing a second ply having at least a first and second radiation sensitive zone overlying the first and second independent indicia of said first ply, respectively;
• the first and second radiation sensitive zones configured to change opacity in response to exposure to a radiation dosage exceeding a predetermined threshold so as to change the visibility of the first and second indicia therethrough;
• and
• providing a third ply overlying the second ply and having at least a first and second viewing zones through which the first and second visible indicia of the first ply are exposed to view, the first and third plies being opaque and having border portions extending beyond the second ply;
• laminating the first ply to the second ply;
• laminating the third ply in overlying relationship to the second ply;
• and
• attaching the border portions of the first and third plies to each other to seal the edge of the second ply from exposure to ambient light.