1. A method for resolving complex conjugate ambiguity in an optical coherence tomography (OCT) interferogram, the method comprising:
producing light from a light source;
producing a phase modulation of the light within a resonator cavity through which the light travels, wherein the resonator cavity is disposed in the light source;
propagating a reference light portion from the light source along a reference arm optical pathlength and a sample light portion from the light source along a sample arm optical pathlength, the reference arm optical pathlength and the sample arm optical pathlength being offset from each other by a multiple of an optical pathlength of the resonator cavity; and
using the phase modulation of the light to separate a positive and a negative displacement of a complex conjugate component of the OCT interferogram produced by combining and detecting the reference light portion and the sample light portion.
2. The method according to claim 1, wherein the light source comprises a laser.
3. The method according to claim 2, wherein the resonator cavity comprises an integral and internal component of the laser.
4. The method according to claim 2, further comprising forming a linear-in-wavelength cavity length variation with the laser.
5. The method according to claim 2, further comprising controlling an axial position shift by adjusting a slope of a cavity length variation.
6. The method according to claim 1, further comprising generating a comb frequency spectrum of the light with the resonator cavity.
7. The method according to claim 1, wherein the sample arm optical pathlength is longer than the reference arm optical pathlength by a multiple of the optical pathlength of the resonator cavity.
8. The method according to claim 1, wherein the reference arm optical pathlength is longer than the sample arm optical pathlength by a multiple of the optical pathlength of the resonator cavity.
9. The method according to claim 1, wherein the phase modulation of the light comprises at least one of a variance in a physical pathlength of the light, a variance in an index of refraction of the light, or a shift in a frequency of the light.
10. The method according to claim 1, further comprising producing the OCT interferogram using a Fourier Domain OCT (FDOCT) system.
11. The method according to claim 10, wherein producing the OCT interferogram comprises producing the OCT interferogram using a Spectral Domain OCT (SDOCT) system.
12. The method according to claim 10, wherein producing the OCT interferogram comprises producing the OCT interferogram using a swept-source OCT (SSOCT) system.
13. The method according to claim 12, wherein the SSOCT system comprises a heterodyne SSOCT system.
14. The method according to claim 1, further comprising applying a numerical dispersion compensation algorithm to the OCT interferogram.
15. The method according to claim 1, further comprising generating a group delay in the reference arm.
16. The method according to claim 15, wherein generating a group delay comprises using a dispersive optical delay line (DODL) in the reference arm.
17. The method according to claim 16, further comprising applying a hardware dispersion compensation to compensate for a group velocity dispersion.
18. The method according to claim 1, wherein the multiple of an optical pathlength of the resonator cavity by which the reference arm optical pathlength and the sample arm optical pathlength are being offset from each other comprises an integer.
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 recording medium with a load distribution program recorded therein for a computer system including a plurality of processors and a plurality of inputoutput devices, the program causing the computer to execute:
acquiring, at a first timing, a processor load status including a processor usage rate of an application job, a processor usage rate of an interrupt from at least one of the inputoutput devices, and a processor usage rate increasingdecreasing tendency for each of the processors; and, for each of the inputoutput devices, an inputoutput device load status including an interrupt destination processor and an accumulated number of times of interrupts;
referencing, at every second timing, a load distribution policy that defines a load distribution initiating condition and a load distribution executing condition for distributing interrupts from at least one of the inputoutput devices among the processors, and using the processor usage rate of the application job, the processor usage rate of the interrupt from the at least one of the inputoutput devices, and the processor usage rate increasingdecreasing tendency; and determining whether or not a processor satisfying the load distribution initiating condition is present based on the processor load status;
referencing the processor load statuses and inputoutput device load statuses when a processor satisfying the load distribution initiating condition is present; calculating processor usage rates of all inputoutput devices interrupting the processor; and determining a processor and an inputoutput device satisfying the load distribution executing condition based on the calculated processor usage rate; and
changing the interrupt destination processor of the inputoutput device satisfying the load distribution executing condition.
2. The recording medium according to claim 1, wherein the load distribution program stored in the recording medium causes the computer to further execute the following processing comprising:
defining in the load distribution policy, a hardware configuration of the computer system that is an application target; and
selecting, for the computer system, a load distribution policy conforming to the hardware configuration, out of a plurality of load distribution policies.
3. The recording medium according to claim 1, wherein the load distribution program stored in the recording medium causes the computer to further execute the following processing comprising:
weighting the processor usage rate of at least one of the inputoutput devices, in accordance with the increasing rate of the number of times of interrupts.
4. The recording medium according to claim 1, wherein the load distribution program stored in the recording medium causes the computer to further execute the following processing comprising:
when determining a processor and an inputoutput device that satisfy the load distribution executing condition, excluding the processor from a determination target until a third timing longer than the second timing elapses, after the processor satisfying the load distribution executing condition has been determined.
5. The recording medium according to claim 1, wherein the load distribution program stored in the recording medium causes the computer to further execute the following processing comprising:
causing the computer system to implement outputting a message for urging an improvement in the load distribution policy when the processor and the inputoutput device that satisfy the load distribution executing condition are unable to be determined a specific number of times.
6. A load distribution apparatus in a computer system including a plurality of processors and a plurality of inputoutput devices, the load distribution apparatus comprising:
a load status acquisition unit for acquiring, every first timing, for each of the processors, a load status including a processor usage rate of an application job, a processor usage rate of an interrupt from at least one of the inputoutput devices, and a processor usage rate increasingdecreasing tendency; and, for each of the inputoutput devices, an inputoutput device load status including an interrupt destination processor and an accumulated number of times of interrupts;
a determination unit for referencing, at every second timing, a load distribution policy that defines a load distribution initiating condition and a load distribution executing condition for distributing interrupts from at least one of the inputoutput devices among the processors, using the processor usage rate of the application job, the processor usage rate of the interrupt from the at least one of the inputoutput devices, and the processor usage rate increasingdecreasing tendency; and determining whether or not a processor satisfying the load distribution initiating condition is present based on the processor load status;
a decision unit for referencing the processor load statuses and inputoutput device load statuses when a processor satisfying the load distribution initiating condition is present; for calculating processor usage rates of all the inputoutput devices interrupting the processor; and for deciding a processor and an inputoutput device satisfying the load distribution executing condition based on the calculated processor usage rate; and
an interrupt destination changing unit for changing an interrupt destination processor of the inputoutput device satisfying the load distribution executing condition.