Quartz crystal unit, quartz crystal oscillator and electronic apparatus

A quartz crystal unit comprising:

• a case;
• a quartz crystal tuning fork resonator;
• and a lid;
• wherein the quartz crystal tuning fork resonator has a quartz crystal tuning fork base, and first and second quartz crystal tuning fork tines connected to the quartz crystal tuning fork base, each of the first and second quartz crystal tuning fork tines comprising a plurality of different widths having a first width and a second width greater than the first width, each of the first and second quartz crystal tuning fork tines having a first main surface and a second main surface opposite the first main surface;
• wherein at least one groove is formed in at least one of the first and second main surfaces of each of the first and second quartz crystal tuning fork tines so that a distance in the width direction of the at least one groove measured from an outer edge of the at least one groove to an outer edge of the corresponding one of the first and second quartz crystal tuning fork tines is less than 0.021 mm;
• and
• wherein the first width of each of the first and second quartz crystal tuning fork tines is greater than 0.03 mm and less than 0.075 mm and the second width of each of the first and second quartz crystal tuning fork tines is greater than 0.04 mm and less than 0.23 mm.

A quartz crystal oscillator comprising:

• a quartz crystal oscillating circuit comprised of a plurality of capacitors, a resistor and a quartz crystal unit having a case, a quartz crystal tuning fork resonator and a lid;
• wherein the quartz crystal tuning fork resonator has a quartz crystal tuning fork base, and first and second quartz crystal tuning fork tines connected to the quartz crystal tuning fork base, each of the first and second quartz crystal tuning fork tines comprising a plurality of different widths having a first width and a second width greater than the first width, each of the first and second quartz crystal tuning fork tines having a first main surface and a second main surface opposite the first main surface;
• wherein at least one groove is formed in at least one of the first and second main surfaces of each of the first and second quartz crystal tuning fork tines so that a distance in the width direction of the at least one groove measured from an outer edge of the at least one groove to an outer edge of the corresponding one of the first and second quartz crystal tuning fork tines is less than 0.021 mm;
• and
• wherein the first width of each of the first and second quartz crystal tuning fork tines is greater than 0.03 mm and less than 0.075 mm and the second width of each of the first and second quartz crystal tuning fork tines is greater than 0.04 mm and less than 0.23 mm.

An electronic apparatus comprising:

• a display portion;
• and
• a quartz crystal oscillator comprised of a plurality of capacitors, a resistor and a quartz crystal unit having a case, a quartz crystal tuning fork resonator and a lid;
• wherein the quartz crystal tuning fork resonator has a quartz crystal tuning fork base, and first and second quartz crystal tuning fork tines connected to the quartz crystal tuning fork base, each of the first and second quartz crystal tuning fork tines comprising a plurality of different widths having a first width and a second width greater than the first width, each of the first and second quartz crystal tuning fork tines having a first main surface and a second main surface opposite the first main surface;
• wherein at least one groove is formed in at least one of the first and second main surfaces of each of the first and second quartz crystal tuning fork tines so that a distance in the width direction of the at least one groove measured from an outer edge of the at least one groove to an outer edge of the corresponding one of the first and second quartz crystal tuning fork tines is less than 0.021 mm;
• wherein the first width of each of the first and second quartz crystal tuning fork tines is greater than 0.03 mm and less than 0.075 mm and the second width of each of the first and second quartz crystal tuning fork tines is greater than 0.04 mm and less than 0.23 mm;
• and
• wherein an output signal of the quartz crystal oscillator comprising the quartz crystal unit having the quartz crystal tuning fork resonator is a clock signal for use in operation of the electronic apparatus to display time information at the display portion.