Bidirectional wavelength division multiplex transceiver module

• US 5,487,124 A
• Filed: 06/30/1994
• Issued: 01/23/1996
• Est. Priority Date: 06/30/1994
• Status: Expired due to Term

• Current Assignee: Kaptron Incorporated, The Whitaker Corporation (Meggitt PLC)
• Original Assignee: The Whitaker Corporation (Meggitt PLC)
• Inventors: Bowen, Terry P., Lewis, Warren H., Bergstrom, Richard C.
• Primary Examiner(s): Bovernick, Rodney B.
• Assistant Examiner(s): Ngo, John
• Application Number:
  US08/269,428
• Time in Patent Office: 572 Days
• Field of Search: 385/89-94, 385/14, 385/49, 385/39
• US Class Current: 385/93
• CPC Class Codes: G02B 6/29361 Interference filters, e.g. multilayer coatings, thin film filters, dichroic splitters or mirrors based on multilayers, WDM filters
• CPC Class Codes: G02B 6/4234 Passive alignment along the optical axis and active alignment perpendicular to the optical axis
• CPC Class Codes: G02B 6/4246 Bidirectionally operating package structures

Abstract

A compact optical transceiver including a ceramic mounting block 1, with a laser diode 3 abutting a first end of the mounting block for generating light of a first wavelength. A GRIN lens 5, mounted to the mounting block, then receives and focuses the generated light to an optical fiber 13 which is attached to the compact optical transceiver. A dichroic substance 7 acts as a beamsplitter by passing light of a first wavelength and deflecting light of a second wavelength. The dichroic substance 7 is coated on a glass plate, which is mounted in a first angular groove of the mounting block. The beamsplitter 7 receives and passes the generated light of the first wavelength which has been focused by the GRIN lens 5. From a remote transmitter, light of a second wavelength is then transmitted through an optical fiber 13, to the compact optical transceiver from a direction opposite that of the light generated by the laser diode 3. The light transmitted from the optical fiber 13 is then transmitted and output through ferrule 11, attachable to the optical fiber and attached in a second, V-shaped, groove of the ceramic mounting block 1. The light of the second wavelength is output to the beamsplitter 7 and is deflected through a bore hole 21 in the ceramic mounting block to a detector 9 abutting the bottom of the mounting block. Optionally, a blocking filter 15 can be included between the detector and the optical fiber end face for blocking light of any wavelengths different from the first and second wavelengths, from reaching the detector 9.

Claims

1. A compact optical transceiver comprising:

a mounting block including at least first and second positioning grooves formed therein;

a light generating means, abutting a first end of the mounting block, for generating light of a first wavelength;

a light focusing means, mounted to the mounting block, for receiving and focusing the generated light to an optical fiber;

a beamsplitting means, mounted in the first positioning groove of the mounting block, for receiving and passing the generated light of the first wavelength and for receiving and deflecting light of a second wavelength different from the first wavelength;

a detecting means, abutting the mounting block, for receiving and detecting the deflected light of the second wavelength; and

a ferrule, attachable to the optical fiber and supported in the second positioning groove of the mounting block, for receiving the focused light of a first wavelength passed through the beamsplitting means and for outputting light of a second wavelength from the optical fiber to the beamsplitting means.

2. The compact optical transceiver of claim 1, wherein the light generating means includes a laser diode.

3. The compact optical transceiver of claim 1, wherein the light generating means is secured between adjustable clamps associated with the mounting block.

4. The compact optical transceiver of claim 3, wherein the clamps are adjustable in at least one of a first direction perpendicular to a direction of travel of the generated light, and a second direction perpendicular to both the first direction and the direction of travel of the generated light.

5. The compact optical transceiver of claim 1, wherein the light generating means generates light of approximately 1.3 μ

m in wavelength.

6. The compact optical transceiver of claim 1, wherein the light focusing means includes a graded refractive index (GRIN) lens.

7. The compact optical transceiver of claim 1, wherein the beamsplitting means includes a dichroic coating on a glass substrate.

8. The compact optical transceiver of claim 1, wherein the beamsplitting means passes light of a wavelength less than or equal to approximately 1.3 μ

m and deflects light of a wavelength greater than or equal to approximately 1.55 μ

m.

9. The compact optical transceiver of claim 1, wherein the detecting means includes a blocking filter for blocking received light of a wavelength greater than 1.62 μ

m from being detected.

10. The compact optical transceiver of claim 1, further including:

filtering means, mounted in a third positioning groove of the mounting block between the beamsplitting means and the ferrule, for blocking light, received from the ferrule, of a third wavelength, different from the first and second wavelength.

11. The compact optical transceiver of claim 10, wherein the filtering means includes a blocking filter for blocking received light of a wavelength greater than 1.62 μ

m from being deflected to the detecting means by the beamsplitting means.

12. The compact optical transceiver of claim 1, wherein the mounting block includes a bore hole, through which the deflected light travels from the beamsplitting means to the detecting means.

13. The compact optical transceiver of claim 1, wherein the second positioning groove of the mounting block is a V-shaped groove, in which the ferrule is adjustable in a direction parallel to the direction of travel of the generated light.

14. The compact optical transceiver of claim 1, wherein the mounting block is ceramic.

15. The compact optical transceiver of claim 1, wherein the first positioning groove includes at least one angled side extending in a direction perpendicular to a direction of travel of light from the generated light.

16. The compact optical transceiver of claim 1, wherein the second positioning groove is a V-shaped groove, including two angled sides extending in a direction parallel to a direction of travel of the generated light.

17. The compact optical transceiver of claim 1, wherein the optical fiber attached to the ferrule includes an end face with a 6°

-9°

face angle.

18. The compact optical transceiver of claim 1, wherein the mounting block, light generating means, light focusing means, beamsplitting means, detecting means, and ferrule are encapsulated in a membrane.

19. A compact optical transceiver comprising:

a ceramic mounting block;

a light source, abutting a first end of the ceramic mounting block, generating light of a first wavelength;

a graded refractive index lens, mounted to the ceramic mounting block, receiving and focusing the generated light into an optical fiber;

a beamsplitter, mounted on the ceramic block, receiving and passing the generated light of the first wavelength and receiving and deflecting light of a second wavelength different from the first wavelength;

a detector, abutting the ceramic block, receiving and detecting the deflected light of the second wavelength; and

a ferrule, attached to the optical fiber and the mounting block, receiving the focused and passed light of a first wavelength and outputting light of a second wavelength from the optical fiber to the beamsplitter.

20. The compact optical transceiver of claim 19, wherein the light source is secured between adjustable clamps of the ceramic mounting block.

21. The compact optical transceiver of claim 20, wherein the clamps are adjustable in at least one of a first direction perpendicular to a direction of travel of the generated light, and a second direction perpendicular to both the first direction and the direction of travel of the generated light.

22. The compact optical transceiver of claim 19, wherein the beamsplitter includes a dichroic coating on the surface of a glass substrate.

23. The compact optical transceiver of claim 19, wherein the beamsplitter passes light of a wavelength less than or equal to approximately 1.3 μ

m and deflects light of a wavelength greater than or equal to approximately 1.55 μ

m.

24. The compact optical transceiver of claim 19, wherein the dichroic coated side of the glass substrate passes light of a wavelength less than or equal to approximately 1.3 μ

m and deflects light of a wavelength greater than or equal to approximately 1.55 μ

m.

25. The compact optical transceiver of claim 19, further including:

filter, mounted on the ceramic mounting block between the glass substrate and the ferrule, for blocking light received from the ferrule of a third wavelength, different from the first and second wavelength.

26. The compact optical transceiver of claim 19, wherein the ceramic mounting block includes a bore hole, through which the deflected light travels from the ferrule-proximate side of the glass element to the detector.

27. The compact optical transceiver of claim 19, wherein the ferrule is disposed for adjustable movement in a direction parallel to the direction of travel of the generated light.

28. The compact optical transceiver of claim 19, wherein the optical fiber attached to the ferrule includes an end face with a 6°

-9°

face angle.

29. The compact optical transceiver of claim 19, wherein the ceramic mounting block, light source, graded refractive index lens, beamsplitter, detector, and ferrule are encapsulated in a membrane.