BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a light source apparatus suitable for an image projection apparatus, such as a liquid crystal projector.

Description of the Related Art

Some image projection apparatuses (referred to as projectors hereinafter) configured to modulate light emitted from a light source with a light modulation element, such as a liquid crystal panel, and to project the light onto a projection surface use a laser diode (LD) as a light source. One of such projectors, as disclosed in Japanese Patent Laid-Open No. (“JP”) 2016-224304, uses a plurality of LDs (blue LD and red LD) that emit light with different wavelengths.

Characteristically, the red LD is more likely to cause an optical damage (COD: Catastrophic Optical Damage) than the blue LD particularly when the temperature is lower. In the light source apparatus using a plurality of red LDs, a certain red LD that malfunctions does not emit the light or generate the heat even though supplied with the drive current, and the temperature of the normal red LD adjacent to the abnormal red LD lowers. As a result, the COD may occur even in the normal red LD.

SUMMARY OF THE INVENTION

The present invention provides a light source apparatus and a projector, each of which can suppress COD of a light source, such as a red LD.

A light source apparatus according to one aspect of the present invention includes a first solid light source, a second solid light source configured to emit light with a wavelength different from that from the first solid light source, and a controller configured to control turning on of the first and second solid light sources. The controller turns on the second solid light source while maintaining turning on the first solid light source after turning on the first solid light source. An image projection apparatus including the light source apparatus also constitutes another aspect of the present invention.

A light source apparatus according to another aspect of the present invention includes a first solid light source, a second solid light source arranged to transfer heat generated when the first solid light source is turned on and configured to emit light with a wavelength different from that of the first solid light source, and a controller configured to control a drive current for turning on each of the first and second solid light sources. In turning on the first and second light sources, the controller increases the drive current of the second solid light source to a set value by taking time longer than that used for the drive current of the first solid light source to increase up to the set value. An image projection apparatus including the light source apparatus also constitutes another aspect of the present invention.

A control method for a light source apparatus according to another aspect of the present invention including a first solid light source, and a second solid light source arranged to transmit heat generated when the first solid light source is turned on, and configured to emit light with a wavelength different from that of the first solid light source includes the steps of turning on the first solid light source, and turning on the second solid light source after turning on the first solid light source. A storage medium storing a program that causes a computer to execute the control method also constitute another aspect of the present invention.

A control method for a light source apparatus according to another aspect of the present invention including a first solid light source, and a second solid light source arranged to transmit heat generated when the first solid light source is turned on, and configured to emit light with a wavelength different from that of the first solid light source, the control method includes the step of controlling a drive current for turning on each of the first and second solid light sources. In turning on the first and second solid light sources, the controlling step increases the drive current of the second solid light source up to a set value by taking time longer than that used for the drive current of the first solid light source to increase up to the set value. A storage medium storing a program that causes a computer to execute the control method also constitute another aspect of the present invention.

Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.

