Supplemental device for attachment to an injection device
A supplemental device for attachment to an injection device including a dosage window covering a sleeve on which dose values are marked is disclosed. The supplemental device comprises a main body; an arrangement for supporting the main body of the supplemental device in a predetermined positional relationship with the injection device; a transparent protection window located at a surface of the main body that is aligned with the dosage window of the injection pen when in use; a sensor arrangement supported in the main body and having a sensor directed at the protection window; an illumination arrangement comprising one or more sources of light, each of the one or more sources of light being directed at the protection window; and a non-transmissive part located on an optical path between a first one of the one or more sources of light.
1. A supplemental device for attachment to an injection device including a dosage window covering a sleeve on which dose values are marked, the supplemental device comprising:
a main body;
an arrangement for supporting the main body of the supplemental device in a predetermined positional relationship with the injection device;
a transparent protection window located at a surface of the main body that is aligned with the dosage window of the injection device when in use;
a sensor arrangement supported in the main body and having a light sensor directed at the protection window;
an illumination arrangement comprising one or more sources of light, each of the one or more sources of light being directed at the protection window; and
a non-transmissive part, wherein the non-transmissive part is located on an optical path between a first one of the one or more sources of light and a point on the dosage window at which reflection to the light sensor would occur and is either provided on a surface of the protection window or is provided within the material forming the protection window.
2. A supplemental device as claimed in claim 1 , wherein the protection window has an optical power.
3. A supplemental device as claimed in claim 1 , wherein the protection window is sealed to the main body so as to prevent the ingress of material into the supplemental device around the protection window.
4. A supplemental device as claimed in claim 1 , wherein the non-transmissive part is provided on a surface of the protection window that is closest to the sensor arrangement.
5. A supplemental device as claimed in claim 4 , wherein the non-transmissive part comprises a blackout spot.
6. A supplemental device as claimed in claim 1 , wherein the non-transmissive part is provided within the material forming the protection window.
7. A supplemental device as claimed in claim 1 , wherein the non-transmissive part is located on an optical path between a first one of the one or more sources of light and a point on a surface of the dosage window that is furthest from the sensor arrangement, the point being a point at which reflection to the sensor arrangement would occur.
8. A supplemental device as claimed in claim 1 , wherein the non-transmissive part is located on an optical path between a first one of the one or more sources of light and a point on a surface of the dosage window that is closest to the sensor arrangement, the point being a point at which reflection to the sensor would occur.
9. A supplemental device as claimed in claim 1 , wherein the illumination arrangement comprises plural sources of light.
10. A supplemental device as claimed in claim 9 , wherein the plural sources of light are located at different positions around the sensor arrangement.
11. A supplemental device as claimed in claim 9 , wherein the plural sources of light are located at different positions around the sensor arrangement and approximately in a plane of a part of the sensor arrangement at which light enters the sensor arrangement.
12. A supplemental device as claimed in claim 9 , wherein the plural sources of light have illumination patterns that are tilted away from a plane of a part of the sensor arrangement at which light enters the sensor arrangement.
13. A supplemental device as claimed in claim 1 , wherein a surface of the protection window that is furthest from the sensor arrangement lies on a curved surface of an imaginary cylinder having an axis coincident with a longitudinal axis of the injection device.
14. A system comprising a supplemental device as claimed in claim 1 and an injection device.
15. A system as claimed in claim 14 , wherein a surface of the protection window that is furthest from the sensor arrangement lies on a curved surface of an imaginary cylinder having an axis coincident with a longitudinal axis of the injection device and wherein the surface of the protection window that is furthest from the sensor arrangement lies in close proximity with a dosage window of the injection device when the supplemental device is installed on the injection device.