Projector and related method for projecting a light beam

A method for projecting a light beam with a projector, the projector comprising a light source, a phosphor wheel and a digital mirror device (DMD), the phosphor wheel having a plurality of color sections, and each of the color sections having a plurality of color subsections, the method comprising:

• the light source projecting a light source beam onto M color subsections of a first color section of the plurality of color sections when the DMD is operated at a first duty cycle, wherein M is a positive integer;
• generating first real brightness of the light beam according to an equation y1=Σi=1Mti(ai)×pi , wherein y1 is the first real brightness, i is an integer ranged from 1 to M, ai, is an intensity of the light source beam projected onto an ith color subsection of the M first color subsections, ti(ai) is a transform rate of the ith color subsection when the light source beam with the intensity ai, is projected onto the ith color subsection, and pi is a time duration the light source projects the light source beam onto the ith color subsection;
• determining whether a first difference between the first real brightness and first target brightness of the light beam is less than a first threshold;
• and
• if the first difference is less than the first threshold, continuing to operate the DMD at the first duty cycle when the light source is projecting the light source beam onto the first color section, and continuing to use the light source to project the light source beam onto the ith color subsection at the intensity ai.

A projector, comprising:

• a light source;
• a phosphor wheel, comprising a first color section having a plurality of first color subsections;
• a control unit, coupled to the light source to control the light source to project a light source beam onto the first color subsections with a first intensity;
• a light sensor, coupled to the control unit and configured to sense first stimulated brightness of some of the first color subsections when the light source is projecting the light source beam onto the first color subsections with the first intensity;
• and
• a storage unit, coupled to the control unit and configured to store a lookup table;
• wherein the control unit generates a plurality of first transform rates associated with the first intensity according to the first stimulated brightness of some of the first color subsections, and the control unit controls the storage unit to record the first transform rates in the lookup table.

A method for projecting a light beam with a projector, the projector comprising a light source, a phosphor wheel and a digital mirror device (DMD), the phosphor wheel having a plurality of color sections, the method comprising:

• the light source projecting a light source beam with a first intensity onto a first color section of the plurality of color sections when the DMD is operated at a first duty cycle;
• generating first real brightness of the light beam;
• determining whether a first difference between the first real brightness and first target brightness of the light beam is less than a first threshold;
• if the first difference is less than the first threshold, continuing to operate the DMD at the first duty cycle and to use the light source to project the light source beam onto the phosphor wheel at the first intensity when the light source is projecting the light source beam onto the first color section;
• and
• if the first difference is greater than the first threshold, using the light source to project the light source beam onto the first color section at a second intensity, and operating the DMD at a second duty cycle when the light source is projecting the light source beam onto the first color section;
• wherein the second duty cycle is different from the first duty cycle and the second intensity is different from the first intensity.