1. A method for selectively characterizing a color marking device relative to a plurality of viewing illuminants for enhanced output image accuracy when illuminated by a predetermined one of the plurality, the method comprising steps of:
building a device transformation profile for mapping a device independent color description signal to a device dependent color description signal, wherein the profile includes a multi-dimensional look-up table (LUT) and a first set of tone reproduction curves (TRCs), and wherein the first set of TRCs is calibrated for a first selected viewing illuminant comprising a selected light source for illuminated viewing of an output image generated by the color marking device;
building a second set of TRCs characterized for a second viewing illuminant; and,
responsive to a user instruction for outputting an image intended for illumination by the second viewing illuminant, adjusting the transformation profile to effect transforming an input color representation signal of the image with the LUT and the second set of TRCs.
2. The method as defined in claim 1 wherein the building the second set of TRCs comprises defining controlled points of the second set of TRCs corresponding to neutral colors.
3. The method as defined in claim 2 wherein the defining controlled points comprises gray balancing the device for different viewing illuminants.
4. The method as defined in claim 1 wherein building the second set of TRCs comprises building a plurality of TRC sets, each corresponding to a different viewing illuminant.
5. The method as defined in claim 2 wherein the building the second set of TRCs comprises interpolating uncontrolled points of the second set of TRCs from the controlled points.
6. A system for characterizing a color marking device relative to a selected viewing illuminant for system output, wherein the viewing illuminant comprises an intended light source for illuminated viewing of a system output image generated by the color marking device comprising:
a profile including a LUT and a first set of TRCs calibrated for accurate color output as viewed under a first viewing illuminant; and,
an adjusted profile including the LUT and a second set of TRCs calibrated for accurate color output as viewed under a second viewing illuminant whereby system characterization for deriving a color correction transformation relative to a plurality of viewing illuminants places reduced demands on system storage for simplified profile management.
7. The system as defined in claim 6 wherein the first and second sets of TRCs comprise a plurality of controlled points generated with reference to a neutral color.
8. The system as defined in claim 7 wherein the neutral color comprises a gray.
9. The system as defined in claim 8 wherein the system comprises a plurality of TRC sets, each corresponding to a different viewing illuminant.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A sputtering power-supply unit comprising:
a voltage generation section which generates a sputtering voltage between a negative electrode output terminal and a positive electrode output terminal; and
a circuit section which reduces fluctuation in a sputtering current even if an arc discharge occurs between the negative electrode output terminal and the positive electrode output terminal.
2. A sputtering power-supply unit according to claim 1, wherein
the voltage generation section comprises:
a sputtering DC power source;
a first switch section disposed on the negative electrode side of the sputtering DC power source;
a second switching section disposed in a middle position between a plurality of mutually independent choke coils serially connected to the first switch means and a reverse-direction arc prevention circuit;
a voltage detection section which detects a voltage generated between the negative electrode output terminal and the positive electrode output terminal; and
a current detection section which detects a current flowing through the choke coils.
3. A sputtering power-supply unit according to claim 2,
wherein the circuit section comprises:
an integration section which integrates an error between set power and power calculated from the voltage detected by the voltage detection section and the current detected by the current detection section;
a differential amplifier which takes an error between a value of the current detected by the current detection section and an output of the integration section as a current set value;
a pulse width varying section which varies a pulse width to control openingclosing of the first switching section in accordance with an output of the differential amplifier; and
means for stopping an operation of the integration section while the second switching section is closed when arc generation is detected based on the voltage detected by the voltage detection section.
4. A sputtering power-supply unit according to claim 2,
wherein the circuit section comprises:
a comparator which has hysteresis to compare the current valued detected by the current detection section with a set current value; and
a driving section which drives the first switching section in accordance with a comparison result of the comparator.
5. A sputtering power-supply unit according to claim 2,
wherein the circuit section comprises:
an integration section which integrates an error between power calculated from the voltage detected by the voltage detection unit and the current detected by the current detection section and set power;
a comparator which has hysteresis to compare a value of the current detected by the current detection section with an output of the integration section as a current set value;
a driving section which drives the first switching section in accordance with a comparison result of the comparator; and
means for stopping an operation of the integration means while the second switching section is closed when arc generation is detected based on the voltage detected by the voltage detection section.
6. A sputtering power-supply unit according to claim 2,
wherein the circuit section comprises:
an arithmetic circuit which divides a value obtained based on the set current value, the current value detected by the current detection means and the voltage detected by the voltage detection circuit by a voltage of the sputtering DC power source; and
a pulse width varying circuit which varies a pulse width to control openingclosing of the first switching section in accordance with an output of the arithmetic circuit.
7. A sputtering power-supply unit according to claim 2,
wherein the circuit section comprises:
an integration section which integrates an error between power calculated from the voltage detected by the voltage detection unit and the current detected by the current detection section and set power;
an arithmetic circuit which divides a value obtained based on a set current value obtained by the integration section, the current value detected by the current detection means and the voltage detected by the voltage detection circuit by a voltage of the sputtering DC power source;
a pulse width varying circuit which varies a pulse width to control openingclosing of the first switching section in accordance with an output of the arithmetic circuit; and
means for stopping an operation of the integration section while the second switching section is closed when arc generation is detected based on the voltage detected by the voltage detection section.
8. A sputtering power-supply unit according to claim 1,
wherein the voltage generation section comprises:
a DC power source which generates a predetermined voltage;
a switching circuit which has a plurality of switching elements connected to bridges, and converts an output of the DC power source into a pulse output;
a transformer which receives a primary pulsed voltage from the switching circuit, and outputs a secondary pulsed voltage;
first and second diode bridges which rectify the secondary pulsed voltage output from the transformer;
a plurality of mutually independent choke coils serially connected to an output side of the first diode bridge;
a reverse voltage holding capacitor connected to an output side of the second diode bridge;
a switching section disposed between the reverse voltage holding capacitor and a middle position between the plurality of serially connected and independent choke coils and the negative electrode output terminal;
a voltage detection section which detects a voltage generated between the negative electrode output terminal and the positive electrode output terminal; and
a current detection circuit which detects a current flowing through the choke coils.
9. A sputtering power-supply unit according to claim 8,
wherein the circuit section comprises:
a comparator which has hysteresis to compare the current detected by the current detection section with a current set value;
an oscillator connected to an output of the comparator; and
a switch control section which responds to an oscillation signal transmitted from the oscillator to output a switching signal to the switching element of the switching circuit while the output of the comparator is at a high level.
10. A sputtering power-supply unit according to claim 8,
wherein the circuit section comprises:
an integration section which integrates an error between power calculated from the voltage detected by the voltage detection unit and the current detected by the current detection section and set power;
a comparator which has hysteresis to compare a value of the current detected by the current detection section with an output of the integration section as a current set value;
an oscillator connected to an output of the comparator;
a switch control section which responds to an oscillation signal transmitted from the oscillator to output a switching signal to a switching element of the switching circuit while the output of the comparator is at a high level; and
means for stopping an operation of the integration section while the switching section is closed when arc generation is detected based on the voltage detected by the voltage detection section.
11. A sputtering power-supply unit according to claim 8,
wherein the circuit section comprises:
an arithmetic circuit which divides a value obtained based on the set current value, the current value detected by the current detection means and the voltage detected by the voltage detection circuit by a voltage of the primary side DC power source to calculate a pulse width; and
a switch control section which outputs a switching signal to a switching element of the switching circuit in accordance with the pulse width output from the arithmetic circuit.
12. A sputtering power-supply unit according to claim 8,
wherein the circuit section comprises:
an integration section which integrates an error between power calculated from the voltage detected by the voltage detection unit and the current detected by the current detection section and set power;
an arithmetic circuit which receives an output of the integration section as a set current value, and divides a value obtained based on the current value detected by the current detection section and the voltage detected by the voltage detection circuit by a voltage of the sputtering DC power source to calculate a pulse width;
a switch control section which outputs a switching signal to a switching element of the switching circuit in accordance with an output of the arithmetic circuit; and
means for stopping an operation of the integration section while the switching section is closed when arc generation is detected based on the voltage detected by the voltage detection section.
13. A sputtering power-supply unit according to claim 8,
wherein the circuit section comprises:
a control section which divides a value obtained based on the set current value, the current value detected by the current detection section and the voltage detected by the voltage detection section by a voltage of the primary side DC power source to calculate a pulse width;
a sample holding circuit which holds the pulse width output from the control section; and
a switch control section which outputs a switching signal to a switching element of the switching circuit in accordance with an output of the sample holding circuit.
14. A sputtering power-supply unit according to claim 8,
wherein the circuit section comprises:
a control section which divides a value obtained based on the set current value, the current value detected by the current detection section and the voltage detected by the voltage detection section by a voltage of the primary side DC power source to calculated a pulse width, and samples and holds the pulse width; and
a switch control section which outputs a switching signal to a switching element of the switching circuit in accordance with an output of the control section.
15. A sputtering power-supply unit according to claim 8,
wherein the circuit section comprises:
a control section which divides a value obtained based on the set current value, the current value detected by the current detection section and the voltage detected by the voltage detection section by a voltage of the primary side DC power source to calculate a pulse width, samples and holds the pulse width, and outputs a switching signal to a switching element of the switching circuit.
16. A sputtering power-supply unit which has a negative electrode output terminal and a positive electrode output terminal, comprising:
a DC power source which generates an output of a predetermined voltage;
a switching circuit which has a plurality of switching elements connected to bridges, and converts an output of the DC power source into a pulse output;
a transformer which receives a primary pulsed voltage from the switching circuit, and outputs a secondary pulsed voltage;
a rectification circuit which rectifies the secondary pulsed voltage output from the transformer;
a choke coil connected to an output side of the rectification circuit;
a reverse voltage generation source;
a switching section disposed between the reverse voltage generation source and the choke coil;
a constant voltage element connected in parallel to the switching section; and
a control section which outputs a switching control signal to the switching element, and a switching control signal to control openingclosing of the switching section.
17. A sputtering power-supply unit according to claim 16,
wherein the constant voltage element and current detection means are serially connected in parallel to the switching section.
18. A sputtering power-supply unit according to claim 16,
wherein the constant voltage element and current detection means are serially connected in parallel to the switching section, and the control section turns OFF the switching element when a current equal tohigher than a set current is detected by the current detection section, and outputs a switching control signal to the switching element when a zero current is detected by the current detection section.
19. A sputtering power-supply unit according to claim 16,
wherein the constant voltage element is a constant voltage power source.