Apparatus for applying medicament to an eye

An apparatus for applying a certain predetermined dosage of a fluid into an eye, comprising:

• a container holding a volume of fluid;
• a first dosage cavity forming member and a second dosage cavity forming member, the second member being movable between:
• a first position, in which the first member and the second member together define a cavity which is in fluid communication with the container;
• a second position, in which the first member and the second member together define a cavity having a certain predetermined volume and in which the cavity is not in fluid communication with the container;
• and a third position in which the volume of the cavity is less than the volume of the cavity in the second position and in which the cavity is not in fluid communication with the container;
• a means for biasing the second dosage cavity forming member to the third position;
• and
• a nozzle which is in fluid communication with the cavity, wherein a dosage of fluid in the cavity is forced through the nozzle and out of the apparatus upon movement of the second member from the first position or from the second position to the third position under the action of the biasing means, and wherein the second member is selectively movable from the third position back to the first position to draw fluid from the container into the cavity after each dosage of fluid is forced through the nozzle out of the apparatus;
• the nozzle including an inner nozzle forming member and an outer nozzle forming member which define an interface at an area of contact between them, the area of contact preventing passage of fluid through the nozzle, and wherein the area of contact is at least partially severed by fluid forced out of the cavity and into the nozzle as the second cavity forming member is forced from the second position to the third position by the biasing means, the area of contact being restored upon expulsion of the fluid from the nozzle.