I claim:
1. A method of fabricating a printhead that includes a substrate, a plurality of nozzles positioned on the substrate and a nozzle guard that is mounted on the substrate to cover the nozzles, the nozzle guard defining a plurality of apertures that are aligned with respective nozzles so that ink ejected from the nozzles can pass through the apertures and onto a print medium, the method including the steps of:
depositing a layer of a sacrificial material onto the substrate to cover the nozzles;
positioning the nozzle guard on the sacrificial material; and
removing the sacrificial material.
2. A method as claimed in claim 1, in which the method includes the step of positioning support struts of the nozzle guard on alignment formations extending from the substrate, subsequent to depositing the layer of sacrificial material on the substrate.
3. A method as claimed in claim 2, which includes the step of interposing a seal between each strut and a respective alignment formation.
4. A method as claimed in claim 1, in which the step of removing the sacrificial material includes the step of carrying out a plasma etching process through at least one of the apertures of the nozzle guard.
5. A method as claimed in claim 4 in which the sacrificial material is removed using an oxygen plasma etch.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An optical module comprising, on the same optical waveguide substrate, a first optical waveguide having transmitted optical signals from a light-emitting element incident thereon and a second optical waveguide guiding received optical signals to a light-receiving element,
wherein the optical module comprises:
optical path conversion means that converts the direction of propagation of optical signals propagating along the second optical waveguide to a first direction spatially divergent from the axis of incidence of the transmitted optical signals going into the first optical waveguide, and guides light arriving from directions different from that of the second optical waveguide in a direction different from the first direction.
2. An optical module comprising, on the same optical waveguide substrate, a light-emitting element, a first optical waveguide optically coupled to the light-emitting element, a light-receiving element, and a second optical waveguide guiding optical signals to the light-receiving element,
wherein the light-receiving element is arranged in a position where the normal to its light-receiving surface is in a spatially divergent relationship with respect to the axis of incidence of optical signals on the first optical waveguide from the light-emitting element,
and comprises optical path conversion means that guides optical signals propagating along the second optical waveguide to the light-receiving surface of the light-receiving element, and ensures that an image of the light-emitting spot of the light-emitting element projected onto a plane comprising the light-receiving surface of the light-receiving element does not overlap with light-receiving surface of the light-receiving element.
3. The optical module according to claim 2, wherein the optical path conversion means comprises a planar reflector.
4. The optical module according to claim 2, wherein the optical path conversion means comprises a concave reflector.
5. The optical module according to claim 2, wherein the optical path conversion means comprises means for performing optical path conversion using differences in the refractive indices of materials.
6. The optical module according to claim 5, wherein the means for performing optical path conversion is formed integrally with the light-receiving element.
7. The optical module according to claim 2, further comprising, on the optical waveguide substrate, a third optical waveguide having an optical fiber optically coupled thereto and optical multiplexingde-multiplexing means that outputs transmitted optical signals from the first optical waveguide to the third optical waveguide and guides received optical signals from the third optical waveguide to the second optical waveguide.
8. The optical module according to claim 7, wherein the optical multiplexingde-multiplexing means includes a slit formed in the optical waveguide substrate and an optical filter that is inserted in the slit, couples transmitted optical signals from the first optical waveguide to the third optical waveguide by passing or reflecting the transmitted optical signals, and couples received optical signals from the third optical waveguide to the second optical waveguide by reflecting or passing the received optical signals.
9. The optical module according to claim 3, further comprising, on the optical waveguide substrate, a third optical waveguide having an optical fiber optically coupled thereto and optical multiplexingde-multiplexing means that outputs transmitted optical signals from the first optical waveguide to the third optical waveguide and guides received optical signals from the third optical waveguide to the second optical waveguide.
10. The optical module according to claim 4, further comprising, on the optical waveguide substrate, a third optical waveguide having an optical fiber optically coupled thereto and optical multiplexingde-multiplexing means that outputs transmitted optical signals from the first optical waveguide to the third optical waveguide and guides received optical signals from the third optical waveguide to the second optical waveguide.
11. The optical module according to claim 5, further comprising, on the optical waveguide substrate, a third optical waveguide having an optical fiber optically coupled thereto and optical multiplexingde-multiplexing means that outputs transmitted optical signals from the first optical waveguide to the third optical waveguide and guides received optical signals from the third optical waveguide to the second optical waveguide.
12. The optical module according to claim 6, further comprising, on the optical waveguide substrate, a third optical waveguide having an optical fiber optically coupled thereto and optical multiplexingde-multiplexing means that outputs transmitted optical signals from the first optical waveguide to the third optical waveguide and guides received optical signals from the third optical waveguide to the second optical waveguide.