1. A data storage device comprising:
a disk;
a head comprising a touchdown sensor;
a fly height actuator (FHA) configured to actuate the head vertically over the disk based on an FHA setting; and
control circuitry configured to:
configure the data storage device into a read mode;
while in the read mode, adjust the FHA setting until the head contacts the disk and measure a touchdown read mode resistance of the touchdown sensor;
configure the data storage device into a write mode and adjust the FHA setting so the head is not contacting the disk;
while in the write mode, measure a non-touchdown write mode resistance of the touchdown sensor; and
estimate a write touchdown FHA setting that will cause the head to contact the disk while in the write mode based on the touchdown read mode resistance and the non-touchdown write mode resistance.
2. The data storage device as recited in claim 1, wherein the control circuitry is further configured to:
while in the write mode, adjust the FHA setting and measure a non-touchdown write mode resistance of the touchdown sensor until the non-touchdown write mode resistance nears the touchdown read mode resistance; and
estimate the write touchdown FHA setting by extrapolating the non-touchdown write mode resistances toward the touchdown read mode resistance.
3. The data storage device as recited in claim 1, wherein the control circuitry is further configured to estimate the write touchdown FHA setting based on a delta from a read touchdown FHA setting that causes the head to contact the disk while in the read mode, wherein the delta is based on the touchdown read mode resistance and the non-touchdown write mode resistance.
4. The data storage device as recited in claim 1, wherein the control circuitry is further configured to:
while in the read mode, measure a non-touchdown read mode resistance of the touchdown sensor for a plurality of the FHA settings; and
estimate the write touchdown FHA setting based on the plurality of non-touchdown read mode resistances of the touchdown sensor.
5. The data storage device as recited in claim 4, wherein the control circuitry is further configured to:
first linear fit the plurality of non-touchdown read mode resistances and generate a delta representing a difference between the read mode FHA setting that causes the head to contact the disk and a FHA setting corresponding to a first intercept of the first linear fit with the touchdown read mode resistance of the touchdown sensor;
while in the write mode, adjust the FHA setting and measure a non-touchdown write mode resistance of the touchdown sensor for a plurality of the FHA settings;
second linear fit the plurality of non-touchdown write mode resistances of the touchdown sensor; and
estimate the write touchdown FHA setting based on the delta and a second intercept of the second linear fit with the touchdown read mode resistance of the touchdown sensor.
6. The data storage device as recited in claim 4, wherein the control circuitry is further configured to:
while in the write mode, adjust the FHA setting and measure a non-touchdown write mode resistance of the touchdown sensor for a plurality of the FHA settings; and
estimate the write touchdown FHA setting based on the plurality of non-touchdown read mode resistances of the touchdown sensor and the plurality of non-touchdown write mode resistances of the touchdown sensor.
7. The data storage device as recited in claim 6, wherein the control circuitry is further configured to:
measure a FHA setting delta between the plurality of non-touchdown read mode resistances of the touchdown sensor and the plurality of non-touchdown write mode resistances of the touchdown sensor; and
estimate the write touchdown FHA setting based on the FHA setting delta.
8. The data storage device as recited in claim 6, wherein the control circuitry is further configured to estimate the write touchdown FHA setting by subtracting the FHA setting delta from the read mode FHA setting that causes the head to contact the disk.
9. The data storage device as recited in claim 1, wherein the control circuitry is further configured to:
while in the read mode, measure at least one non-touchdown read mode resistance of the touchdown sensor;
measure an FHA delta setting between the non-touchdown read mode resistance of the touchdown sensor and the non-touchdown write mode resistance of the touchdown sensor; and
estimate the write touchdown FHA setting based on the FHA setting delta.
10. The data storage device as recited in claim 9, wherein the control circuitry is further configured to estimate the write touchdown FHA setting by subtracting the FHA setting delta from the read mode FHA setting that causes the head to contact the disk.
11. The data storage device as recited in claim 1, wherein the control circuitry is further configured to:
while in the write mode, measure at least one touchdown write mode resistance of the touchdown sensor;
measure a slope of a line passing through the touchdown write mode resistance and the touchdown read mode resistance; and
estimate the write touchdown FHA setting based on the slope of the line.
12. A method of operating a data storage device, the method comprising:
configuring the data storage device into a read mode;
while in the read mode, adjusting a fly height actuator (FHA) setting until a head contacts a disk and measuring a touchdown read mode resistance of a touchdown sensor;
configuring the data storage device into a write mode and adjust the FHA setting so the head is not contacting the disk;
while in the write mode, measuring a non-touchdown write mode resistance of the touchdown sensor; and
estimating a write touchdown FHA setting that will cause the head to contact the disk while in the write mode based on the touchdown read mode resistance and the non-touchdown write mode resistance.
13. The method as recited in claim 12, further comprising:
while in the write mode, adjusting the FHA setting and measuring a non-touchdown write mode resistance of the touchdown sensor until the non-touchdown write mode resistance nears the touchdown read mode resistance; and
estimating the write touchdown FHA setting by extrapolating the non-touchdown write mode resistances toward the touchdown read mode resistance.
14. The method as recited in claim 12, further comprising estimating the write touchdown FHA setting based on a delta from a read touchdown FHA setting that causes the head to contact the disk while in the read mode, wherein the delta is based on the touchdown read mode resistance and the non-touchdown write mode resistance.
15. The method as recited in claim 12, further comprising:
while in the read mode, measuring a non-touchdown read mode resistance of the touchdown sensor for a plurality of the FHA settings; and
estimating the write touchdown FHA setting based on the plurality of non-touchdown read mode resistances of the touchdown sensor.
16. The method as recited in claim 15, further comprising:
first linear fitting the plurality of non-touchdown read mode resistances and generating a delta representing a difference between the read mode FHA setting that causes the head to contact the disk and a FHA setting corresponding to a first intercept of the first linear fitting with the touchdown read mode resistance of the touchdown sensor;
while in the write mode, adjusting the FHA setting and measuring a non-touchdown write mode resistance of the touchdown sensor for a plurality of the FHA settings;
second linear fitting the plurality of non-touchdown write mode resistances of the touchdown sensor; and
estimating the write touchdown FHA setting based on the delta and a second intercept of the second linear fitting with the touchdown read mode resistance of the touchdown sensor.
17. The method as recited in claim 15, further comprising:
while in the write mode, adjusting the FHA setting and measuring a non-touchdown write mode resistance of the touchdown sensor for a plurality of the FHA settings; and
estimating the write touchdown FHA setting based on the plurality of non-touchdown read mode resistances of the touchdown sensor and the plurality of non-touchdown write mode resistances of the touchdown sensor.
18. The method as recited in claim 17, further comprising:
measuring an FHA setting delta between the plurality of non-touchdown read mode resistances of the touchdown sensor and the plurality of non-touchdown write mode resistances of the touchdown sensor; and
estimating the write touchdown FHA setting based on the FHA setting delta.
19. The method as recited in claim 17, further comprising estimating the write touchdown FHA setting by subtracting the FHA setting delta from the read mode FHA setting that causes the head to contact the disk.
20. The method as recited in claim 12, further comprising:
while in the read mode, measuring at least one non-touchdown read mode resistance of the touchdown sensor;
measuring an FHA delta setting between the non-touchdown read mode resistance of the touchdown sensor and the non-touchdown write mode resistance of the touchdown sensor; and
estimating the write touchdown FHA setting based on the FHA setting delta.
21. The method as recited in claim 20, further comprising estimating the write touchdown FHA setting by subtracting the FHA setting delta from the read mode FHA setting that causes the head to contact the disk.
22. The method as recited in claim 12, further comprising:
while in the write mode, measuring at least one touchdown write mode resistance of the touchdown sensor;
measuring a slope of a line passing through the touchdown write mode resistance and the touchdown read mode resistance; and
estimating the write touchdown FHA setting based on the slope of the line.
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 transreflective liquid crystal display comprising:
a first insulating substrate;
a color filter substrate including at least four color filters constituting a unit pixel formed on the first insulating substrate, the color filter substrate representing colors using light coming from outside;
a second insulating substrate;
a thin film transistor substrate facing the color filter substrate, the thin film transistor substrate including a thin film transistor, a light transmitting electrode, and a light reflective electrode, each of the thin film transistor, the light transmitting electrode, and the light reflective electrode sequentially forming a respective, distinct layer disposed on the second insulating substrate;
a light transmitting hole formed in at least one of the color filters at a location corresponding to the light reflective electrode; and
a liquid crystal layer interposed between the color filter substrate and the thin film transistor substrate,
wherein the at least four color filters include red, green, blue, and white color filters,
the light transmitting hole is formed in the red, green, and blue color filters, respectively, and
a size of the light transmission hole of the green color filter is larger than a size of the light transmitting hole of the red color filter, and the size of the light transmitting hole of the red color filter is larger than a size of the light transmitting hole of the blue color filter.
2. The transreflective liquid crystal display of claim 1, wherein a material for forming the white color filter is filled in each of the light transmitting holes formed in the red, green, and blue color filters.
3. A method of manufacturing a transreflective liquid crystal display comprising:
providing a first insulating substrate;
providing a color filter substrate including at least four color filters, that constitute a unit pixel on the first insulating substrate;
providing a second insulating substrate; and
providing a thin film transistor substrate including a thin film transistor, a light transmitting electrode, and a light reflective electrode, each of the thin film transistor, the light transmitting electrode, and the light reflective electrode sequentially forming a respective, distinct layer disposed on the second insulating substrate,
wherein the at least four color filters include red, green, blue, and white color filters,
a light transmitting hole is formed in the red, green, and blue color filters, respectively, and
a size of the light transmission hole of the green color filter is larger than a size of the light transmitting hole of the red color filter, and the size of the light transmitting hole of the red color filter is larger than a size of the light transmitting hole of the blue color filter.
4. The method of claim 3, wherein a material for forming the white color filter is filled in each of the light transmitting holes formed in the red, green, and blue color filters.
5. The transreflective liquid crystal display of claim 1, wherein the light reflective electrode is formed on the light transmitting electrode at an entire area in the transmission hole.
6. The method of claim 3, wherein the light reflective electrode is formed on the light transmitting electrode at an entire area in the transmission hole.