1. A light-emitting element comprising:
a light amplification unit having a function of amplifying light; and
an external resonator connected to said light amplification unit,
said external resonator comprising:
a planar light waveguide arranged inside said external resonator; and
a stress application unit which applies stress directly or indirectly to at least a partial region of said planar light waveguide.
2. An element according to claim 1, wherein said stress application unit is arranged at one of a position immediately above said planar light waveguide and a position shifted from the position immediately above said planar light waveguide.
3. An element according to claim 1, wherein said stress application unit is essentially made of a piezoelectric material.
4. An element according to claim 1, wherein
said external resonator further comprises an optical circuit unit including a planar light waveguide, and
said stress application unit applies stress directly or indirectly to at least a partial region of said optical circuit unit.
5. An element according to claim 4, wherein said optical circuit unit has a reflection function of returning, to said light amplification unit, light output from said light amplification unit.
6. An element according to claim 4, wherein said optical circuit unit has a reflection function of returning, of light output from said light amplification unit, only a light component having a specific wavelength to said light amplification unit.
7. An element according to claim 6, wherein said external resonator further comprises a wavelength control unit which controls the specific light wavelength returned to said light amplification unit by said optical circuit unit.
8. An element according to claim 1, further comprising a stress control unit which controls a magnitude of the stress applied to said planar light waveguide by said stress application unit.
9. An element according to claim 8, further comprising an emission state monitor which measures an emission state of the light-emitting element,
wherein said stress application unit controls the magnitude of the stress on the basis of information form said emission state monitor.
10. An element according to claim 9, wherein said emission state monitor comprises an emission power monitor which measures an emission power of the light-emitting element.
11. An element according to claim 10, wherein said stress application unit controls the magnitude of the stress to maximize the emission power of the light-emitting element.
12. An element according to claim 4, wherein said external resonator further comprises a substrate with said optical circuit unit being formed, the substrate having a region where said light amplification unit is to be mounted.
13. An element according to claim 12, further comprising:
a first alignment mark formed in the region where said light amplification unit is to be mounted; and
a second alignment mark formed at a position corresponding to said first alignment mark in said light amplification unit.
14. An element according to claim 12, wherein said light amplification unit is mounted while directing a side with an active layer of said light amplification unit to the region where said light amplification unit is to be mounted.
15. An element according to claim 1, wherein said planar light waveguide and said stress application unit are monolithically integrated.
16. An element according to claim 1, wherein
said planar light waveguide has a bent waveguide portion which passes through, a plurality of number of times, a region where said stress application unit is arranged, and
said stress application unit applies stress to the bent waveguide portion.
17. A light-emitting element including a laser,
said laser comprising:
a light amplification unit having a function of amplifying light;
a planar light waveguide arranged inside an external resonator; and
a stress application unit which applies stress directly or indirectly to at least a partial region of said planar light waveguide.
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. A method of transmitting printer information which a host needs to use in order to communicate with a network printer to the host connected to the network printer, in the network printer, the method comprising;
comparing printer information set the network printer with the inputted printer information;
determining whether printer information is changed or not based on the comparison result; and
transmitting the changed printer information from the network printer to a communications network or a predetermined program that communicates with the network printer, if printer information is changed,
wherein the transmitted printer information includes information which is required by the host to establish subsequent communication with the network printer.
2. The method of claim 1, wherein the transmitting comprises:
packeting the changed printer information; and
transmitting the packetized printer information to the communications network or the predetermined program by broadcasting, multicasting, or unicasting.
3. The method of claim 1, wherein the predetermined program is installed in the host.
4. The method of claim 1, wherein the transmitted printer information comprises an IP address associated with the network printer, which has been recently changed.
5. The method of claim 1, wherein the transmitted printer information comprises subnet mask information associated with the network printer, which has been recently changed.
6. The method of claim 1, wherein the transmitted printer information comprises gateway information associated with the network printer, which has been recently changed.
7. The method of claim 1, wherein: the transmitting comprises:
transmitting the changed printer information from the network printer to a communications network or a predetermined program that communicates with the network printer, if printer information is changed without a request from the host.
8. A network printer which transmits printer information which a host needs to use in order to communicate with the network printer to the host connected to the network printer, comprising:
a printer information change determination circuit which compares printer information set the network printer with the inputted printer information and determines whether printer information is changed or not based on the comparison result; and
a changed information notification module which transmits the changed printer information to a communications network or a predetermined program which communicates with the network printer, if printer information change determination circuit determines that printer information is changed,
wherein the transmitted printer information includes information which is required by the host to establish subsequent communication with the network printer.
9. The network printer of claim 8, wherein the changed printer information is packetized and transmitted to the communications network or the predetermined program by broadcasting, multicasting, or unicasting.
10. The network printer of claim 8, wherein the predetermined program is installed in the host.
11. The network printer of claim 8, wherein the transmitted printer information comprises an IP address associated with the network printer, which has been recently changed.
12. The network printer of claim 8, wherein the transmitted printer information comprises subnet mask information associated with the network printer, which has been recently changed.
13. The network printer of claim 8, wherein the transmitted printer information comprises gateway information associated with the network printer, which has been recently changed.
14. The network printer of claim 8, wherein the changed information notification module transmits the changed printer information to the communications network or the predetermined program when the network printer is turned on.
15. The printing network of claim 8, wherein the changed printer information is transmitted in a packet having a network protocol comprising a User Datagram Protocol, Transmission Control Protocol, Internetwork Packet eXchange, or sequence Packet eXchange.
16. The network printer of claim 8, wherein the changed information notification module transmits the changed printer information to the communications network or the predetermined program without a request of the host.