Apparatus for optically determining and electronically recording injection doses in syringes

In combination with a syringe, an apparatus for determining and recording a dose of an agent delivered with said syringe, said syringe being of the type comprising:

• a) a barrel for holding said agent, said barrel having an injection end;
• b) a plunger movably positioned in said barrel for expelling said agent, said plunger having a variable color marking whose color varies along the direction of the longitudinal axis of said plunger such that the color of said variable color marking at a predetermined distance from said injection end varies in dependence upon the position of said plunger in said barrel;
• said apparatus comprising:
• a) an optical measuring means for measuring the color of said variable color marking at said predetermined distance from said injection end;
• b) a circuit means connected to said optical measuring means for determining said dose from the measured color;
• and
• c) a recording means connected to said circuit means for recording said dose;
• and
• d) alignment means for aligning the syringe with the optical measuring means, said alignment means having a well-like portion retaining the syringe injection end such that fluids may cannot pass therethrough.