Film cartridge with film related indicator

A film cartridge comprises a cartridge shell for housing a filmstrip, and a coded mechanism for providing an indication of one or more properties of the filmstrip. The coded mechanism includes a cavity formed in the outside of the shell to be accessible, a cover affixed to the outside of the shell that completely covers the cavity, and at least one cut-out in the cover uniquely positioned over the cavity to permit entry into the cavity only through the cut-out to provide an indication of one or more properties of a filmstrip housed in the shell.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention relates generally to the field of photography, and in 
particular to a film cartridge having coded means indicative of one or 
more film characteristics such as film speed. 
2. Description of the Prior Art 
It is well known for a 35 mm film cartridge to include coded means 
indicative of one or more film characteristics such as film speed. 
According to one example, the commercially available KODAK DX 35 mm film 
cartridge has a series of six patches or areas located on the outside of 
the cartridge shell. Patch no. 1 is conductive for every available film 
speed since it is intended to serve as a common area or ground for sensing 
by a corresponding electrical probe in a camera designed for use with the 
DX cartridge. Patches no. 2-6 are selectively conductive or non-conductive 
for sensing by respective electrical probes in the camera to provide 
binary encodements of respective film speeds as ISO speed values or the 
equivalent DIN speed values. An insulative paint covers those patches 
selected to be non-conductive to prevent them from being conductive. 
Further details of the DX cartridge are disclosed in U.S. Pat. No. 4,982, 
209, issued Jan. 1, 1991. 
Another example of a film cartridge with a film speed encodement is 
disclosed in U.S. Pat. No. 3,444,795, issued May 20, 1969. In this 
instance, the cartridge shell has a series of equally spaced locations 
each one of which either is notched or is not notched for sensing by 
mechanical probes in a camera to provide binary encodements of respective 
film speeds. 
SUMMARY OF THE INVENTION 
According to the invention, a film cartridge comprising a cartridge shell 
for housing a filmstrip, and coded means for providing an indication of 
one or more properties of the filmstrip, is characterized in that: 
said coded means includes an exterior cavity formed in the outside of the 
shell to be accessible, a cover affixed to the outside of the shell that 
covers the cavity, and at least one cut-out in the cover uniquely 
positioned over the cavity and smaller than the cavity to permit access to 
the cavity only through the cut-out and to provide an indication of one or 
more properties of a filmstrip housed in the shell.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
The invention is disclosed as being embodied preferably in a 35 mm film 
cartridge. Because the features of this type of film cartridge are well 
known, the description which follows is directed in particular to elements 
forming part of or cooperating directly with the disclosed embodiment. It 
is to be understood, however, that other elements not specifically shown 
or described may take various forms known to persons of ordinary skill in 
the art. 
Referring now to the drawings, FIG. 1 shows a 35 mm film cartridge 1 
comprising a lighttight cartridge shell 3 for housing a filmstrip 5. The 
filmstrip 5 is stored in roll form on a spool 7 supported for rotation 
inside the shell 3 in film unwinding and winding directions. A slit-like 
passageway (not shown) in the shell 3 permits movement of the filmstrip 5 
into and out of the shell. 
According to the invention, a cavity 9 is formed in the outside of the 
shell 3 to be accessible by one or more mechanical probes or sensors (not 
shown) in a camera when the film cartridge 1 is loaded into the camera. A 
cover, preferably a film information label 11, is affixed to the outside 
of the shell 3 to cover the cavity 9. See FIG. 1. The label 11 has at 
least one cut-out, preferably a hole 13, uniquely positioned over the 
cavity 9 to permit a corresponding probe in the camera to enter the cavity 
only through the hole. Thus, the hole 13 can serve as a binary indication 
of one or more properties of the filmstrip 5, such as film speed, as is 
taught by the prior art. 
FIG. 2 shows the label 11 with the hole 13 and a second hole 15 to provide 
a different binary indication than is depicted in FIG. 1. In this 
instance, corresponding probes in the camera would enter the cavity 9 
through the respective holes 13 and 15. 
FIG. 3 shows the label 11 with a hole 17 that encompasses the two holes 13 
and 15. The hole 17 is intended to provide the same binary indication as 
is depicted in FIG. 2. 
The arrangement of the mechanical probes in the camera can vary as is known 
in the prior art. For example, a single probe can be used to detect the 
presence or absence of the hole 13. The absence of the hole 13 would 
provide a binary "0" to indicate an ISO speed value less than 400, and the 
presence of the hole would provide a binary "1" to indicate an ISO speed 
value of 400 or greater. Similarly, respective probes can be use to detect 
the presence or absence of the holes 13 and 15. The absence of the holes 
13 and 15 would provide binary "0, 0" to indicate an ISO speed value of 
25. The absence of the hole 13 and the presence of the hole 15 would 
provide binary "0, 1" to indicate an ISO speed value of 100. The presence 
of the hole 13 and the absence of the hole 15 would provide binary "1, 0" 
to indicate an ISO speed value of 400. The presence of the holes 13 and 15 
would provide binary "1, 1" to indicate an ISO speed value of 1600. Of 
course, to indicate more ISO speed values more holes and corresponding 
probes would be included. 
The invention has been described with reference to a preferred embodiment 
and an alternate embodiment. However, it will be appreciated that 
variations and modifications can be effected within the ordinary skill in 
the art without departing from the scope of the invention. For example, 
instead of the holes 13 and 15 in the label 11, notches can be cut in the 
label which like the holes open to the cavity 9.