1. A color lighting control method for improving image quality of a vision system comprising a lighting device having a plurality of lighting units for irradiating lights of different wavelengths to an inspection subject and a lighting control unit for controlling a light irradiation intensity by respectively adjusting input voltages applied to the lighting units and a camera for shooting an image of the inspection subject to generate a monochrome digital image, the method comprising the steps of:
(a) applying predetermined input voltages to the plurality of lighting units respectively;
(b) obtaining image data through the camera;
(c) calculating an image histogram that is a distribution graph for displaying the number of pixels corresponding to each monochrome level intensity through the image data;
(d) calculating a standard deviation of the image histogram; and
(e) calculating an optimal input voltage value for each of the plurality of lighting units within an adjustment range of the predetermined input voltages, wherein the optimal input voltage value maximizes the standard deviation.
2. The color lighting control method of claim 1, wherein, in the step (e), an input voltage value that maximizes the standard deviation, from among input voltage values obtained through repetition of the steps (b), (c) and (d) while applying a plurality of input voltages adjusted at a predetermined interval to the plurality of lighting units respectively, is calculated as the optimal input voltage value.
3. The color lighting control method of claim 1, wherein, in the step (e), the optimal input voltage value that maximizes the standard deviation is calculated through a steepest decent method in which an operation of calculating an amount of change of the standard deviation according to an input voltage change and applying the input voltage adjusted in consideration of the calculated change amount is repeated.
4. The color lighting control method of claim 1, wherein, in the step (e), the optimal input voltage value that maximizes the standard deviation is calculated through a golden section search method in which an operation of applying a plurality of input voltages adjusted at a predetermined first interval to the plurality of lighting units respectively, re-applying the plurality of input voltages adjusted to be increased or decreased by a second interval smaller than the first interval with respect to the input voltage that maximizes the standard deviation, and calculating the standard deviation for each input voltage is repeated at least once.
5. A color lighting control method for improving image quality of a vision system comprising a lighting device having a plurality of lighting units for irradiating lights of different wavelengths to an inspection subject and a lighting control unit for controlling a light irradiation intensity by respectively adjusting input voltages applied to the lighting units and a camera for shooting an image of the inspection subject to generate a monochrome digital image, the method comprising the steps of:
(a\u2032) applying predetermined input voltages to the plurality of lighting units respectively;
(b\u2032) obtaining image data through the camera;
(c\u2032) calculating an image histogram that is a distribution graph for displaying the number of pixels corresponding to each monochrome level intensity through the image data;
(d\u2032) calculating a maximum value of the image histogram; and
(e\u2032) calculating an optimal input voltage value for each of the plurality of lighting units within an adjustment range of the predetermined input voltages, wherein the optimal input voltage value maximizes the maximum value.
6. The color lighting control method of claim 5, wherein, in the step (d\u2032), the maximum value is calculated within bottom 85-95% of the entire range of the monochrome level intensity.
7. The color lighting control method of claim 5, wherein, in the step (d\u2032), the maximum value is calculated within top 85-95% of the entire range of the monochrome level intensity.
8. The color lighting control method of claim 5, wherein, in the step (d\u2032), the maximum value is calculated within middle 70-90% of the entire range of the monochrome level intensity excluding top 5-15% and bottom 5-15% thereof.
9. The color lighting control method of claim 5, wherein, in the step (e\u2032), an input voltage value that maximizes the maximum value, from among input voltage values obtained through repetition of the steps (b\u2032), (c\u2032) and (d\u2032) while applying a plurality of input voltages adjusted at a predetermined interval to the plurality of lighting units respectively, is calculated as the optimal input voltage value.
10. The color lighting control method of claim 5, wherein, in the step (e\u2032), the optimal input voltage value that maximizes the maximum value is calculated through a steepest decent method in which an operation of calculating an amount of change of the standard deviation according to an input voltage change and applying the input voltage adjusted in consideration of the calculated change amount is repeated.
11. The color lighting control method of claim 5, wherein, in the step (e\u2032), the optimal input voltage value that maximizes the maximum value is calculated through a golden section search method in which an operation of applying a plurality of input voltages adjusted at a predetermined first interval to the plurality of lighting units respectively, re-applying the plurality of input voltages adjusted to be increased or decreased by a second interval smaller than the first interval with respect to the input voltage that maximizes the maximum value, and calculating the standard deviation for each input voltage is repeated at least once.
12. The color lighting control method of claim 6, wherein, in the step (e\u2032), an input voltage value that maximizes the maximum value, from among input voltage values obtained through repetition of the steps (b\u2032), (c\u2032) and (d\u2032) while applying a plurality of input voltages adjusted at a predetermined interval to the plurality of lighting units respectively, is calculated as the optimal input voltage value.
13. The color lighting control method of claim 6, wherein, in the step (e\u2032), the optimal input voltage value that maximizes the maximum value is calculated through a steepest decent method in which an operation of calculating an amount of change of the standard deviation according to an input voltage change and applying the input voltage adjusted in consideration of the calculated change amount is repeated.
14. The color lighting control method of claim 6, wherein, in the step (e\u2032), the optimal input voltage value that maximizes the maximum value is calculated through a golden section search method in which an operation of applying a plurality of input voltages adjusted at a predetermined first interval to the plurality of lighting units respectively, re-applying the plurality of input voltages adjusted to be increased or decreased by a second interval smaller than the first interval with respect to the input voltage that maximizes the maximum value, and calculating the standard deviation for each input voltage is repeated at least once.
15. The color lighting control method of claim 7, wherein, in the step (e\u2032), an input voltage value that maximizes the maximum value, from among input voltage values obtained through repetition of the steps (b\u2032), (c\u2032) and (d\u2032) while applying a plurality of input voltages adjusted at a predetermined interval to the plurality of lighting units respectively, is calculated as the optimal input voltage value.
16. The color lighting control method of claim 7, wherein, in the step (e\u2032), the optimal input voltage value that maximizes the maximum value is calculated through a steepest decent method in which an operation of calculating an amount of change of the standard deviation according to an input voltage change and applying the input voltage adjusted in consideration of the calculated change amount is repeated.
17. The color lighting control method of claim 7, wherein, in the step (e\u2032), the optimal input voltage value that maximizes the maximum value is calculated through a golden section search method in which an operation of applying a plurality of input voltages adjusted at a predetermined first interval to the plurality of lighting units respectively, re-applying the plurality of input voltages adjusted to be increased or decreased by a second interval smaller than the first interval with respect to the input voltage that maximizes the maximum value, and calculating the standard deviation for each input voltage is repeated at least once.
18. The color lighting control method of claim 8, wherein, in the step (e\u2032), an input voltage value that maximizes the maximum value, from among input voltage values obtained through repetition of the steps (b\u2032), (c\u2032) and (d\u2032) while applying a plurality of input voltages adjusted at a predetermined interval to the plurality of lighting units respectively, is calculated as the optimal input voltage value.
19. The color lighting control method of claim 8, wherein, in the step (e\u2032), the optimal input voltage value that maximizes the maximum value is calculated through a steepest decent method in which an operation of calculating an amount of change of the standard deviation according to an input voltage change and applying the input voltage adjusted in consideration of the calculated change amount is repeated.
20. The color lighting control method of claim 8, wherein, in the step (e\u2032), the optimal input voltage value that maximizes the maximum value is calculated through a golden section search method in which an operation of applying a plurality of input voltages adjusted at a predetermined first interval to the plurality of lighting units respectively, re-applying the plurality of input voltages adjusted to be increased or decreased by a second interval smaller than the first interval with respect to the input voltage that maximizes the maximum value, and calculating the standard deviation for each input voltage is repeated at least once.
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. Rotary control element, comprising a control element body and a rotary button mounted so as to be rotatable about at least one axis of rotation, wherein the control element body and the rotary button cooperate such that a first associated switching function is provided by rotating the rotary button, wherein the rotary button is mounted so as to be displaceable relative to the control element body in at least one direction which is substantially perpendicular relative to the axis of rotation, with at least one additional switching function being provided.
2. Rotary control element according to claim 1, wherein the rotary button is mounted so as to be displaceable relative to the control element body in two directions which are substantially perpendicular relative to the axis of rotation, preferably freely displaceable in a plane perpendicular relative to the axis of rotation, so that the functional capability of a joystick is provided.
3. Rotary control element according to claim 2, wherein, in order to provide the functional capability of the joystick, a universal joint is provided for transmitting the displacement of the rotary button onto associated switching or regulating elements of the control element body.
4. Rotary control element according to claim 1, wherein the rotary button is displaceably mounted by means of roller bearings.
5. Rotary control element according to claim 1, wherein the rotary button is displaceably mounted by means of ball bearings.
6. Rotary control element according to claim 1, wherein the bearing for displacing the rotary button is disposed underneath the rotary button, preferably within a cavity defined by the rotary button.
7. Rotary control element according to claim 1, wherein mechanical means for resetting the rotary button into a rest position in the displacement direction of the rotary button are provided.
8. Rotary control element according to claim 1, wherein the rotary button is provided with a substantially disc-shaped inner part, which is displaceably accommodated in a cage.
9. Rotary control element according to claim 8, wherein the substantially disc-shaped inner part is mounted so as to be respectively displaceable relative to the surfaces of the cage adjoining in the direction of the axis of rotation by means of at least three, preferably evenly spaced, balls or pairs of balls.
10. Rotary control element according to claim 1, wherein the substantially disc-shaped inner part andor the cage are manufactured from a zinc-aluminum-magnesium-copper alloy.
11. Motor vehicle, comprising a rotary control element according to claim 1.