Wavelength conversion laser light source, laser light source device and two-dimensional image display device adopting the same, and method of setting temperature of wavelength conversion element

A wavelength conversion laser light source, comprising:

• a fundamental wave laser light source;
• a wavelength conversion element for converting a fundamental wave emitted from the fundamental wave laser light source into a harmonic wave, the wavelength conversion element being made of a material whose light absorption properties are subjected to change according to an output level of a harmonic wave;
• an output setting section for setting a harmonic wave output power value;
• and
• an element temperature switching section that switches a temperature of the wavelength conversion element according to a harmonic wave output level as set in the output setting section,
• wherein the element temperature switch section includes an element temperature holding section that holds the wavelength conversion element at the temperature as switched by the element temperature switching section,
• the wavelength conversion element has a beam diameter variable structure for varying a beam diameter of a harmonic wave outputted from the wavelength conversion element,
• the wavelength conversion laser light source further comprises a beam shape abnormality detection mechanism for detecting an abnormality in beam shape of the harmonic wave outputted from the wavelength conversion element,
• the wavelength conversion element having the beam diameter variable structure is a MgO:
• LiTaO3 crystal element having a periodical polarization inversion structure;
• and
• the harmonic wave has an output power of higher than 1.6 W and less than 6.5 W so that an abnormality in beam shape does not occur.

A wavelength conversion laser light source, comprising:

• a fundamental wave laser light source;
• a wavelength conversion element for converting a fundamental wave emitted from the fundamental wave laser light source into a harmonic wave, the wavelength conversion element being made of a material whose light absorption properties are subjected to change according to an output level of a harmonic wave;
• an output setting section for setting a harmonic wave output power value;
• and
• an element temperature switching section that switches a temperature of the wavelength conversion element according to a harmonic wave output level as set in the output setting section,
• wherein the element temperature switch section includes an element temperature holding section that holds the wavelength conversion element at the temperature as switched by the element temperature switching section,
• the wavelength conversion element has a beam diameter variable structure for varying a beam diameter of a harmonic wave outputted from the wavelength conversion element,
• the wavelength conversion laser light source further comprising a beam shape abnormality detection mechanism for detecting an abnormality in beam shape of the harmonic wave outputted from said wavelength conversion element,
• the beam shape abnormality detection mechanism includes a photoreceptor that monitors an intensity of the harmonic wave outputted from the wavelength conversion element,
• the photoreceptor includes a beam diameter detection mechanism for detecting an abnormality in beam diameter of the harmonic wave outputted from the wavelength conversion element,
• the beam diameter detection mechanism includes a photodiode divided into segments, and
• the beam shape abnormality detection mechanism detects a doughnut shape as the abnormality in beam shape using the photodiode.