Projection device and method for controlling projection device
In a pixel circuit including a first capacitance element and a second capacitance element, in a writing sub-frame, a voltage corresponding to a gray scale level is held in a first capacitance element, a plurality of OLEDs are off in a vertical scanning line flyback period after the writing sub-frame, and in a light-emitting sub-frame after the vertical scanning line flyback period, a current corresponding to the voltage held in the first capacitance element is supplied to the OLED, and the voltage corresponding to the gray scale level is held in the second capacitance element. In an optical path shifting element, an optical path is shifted in the vertical scanning line flyback period, and in the light-emitting sub-frame, the optical path is stabilized.
1. A projection device, comprising:
a display panel including a pixel circuit including a first capacitance element and a second capacitance element, and a light-emitting element that emits light, having luminance corresponding to a current, in a predetermined direction, wherein in a first period, a voltage corresponding to a current supplied to the light-emitting element is held in the first capacitance element, in a light-out period after the first period, the light-emitting element is off, in a second period after the light-out period, a current corresponding to the voltage held in the first capacitance element is supplied to the light-emitting element, and a voltage corresponding to the current supplied to the light-emitting element is held in the second capacitance element; and
an optical path shifting element configured to shift an optical path of light emitted from the light-emitting element to a first and second optical paths, wherein shifting is performed from the first optical path to the second optical path in the light-out period, and the second optical path is maintained in the second period.
2. The projection device according to claim 1 , wherein
in the first period,
a current corresponding to the voltage held in the second capacitance element is supplied to the light-emitting element, and
the first optical path is maintained.
3. The projection device according to claim 2 , wherein
the pixel circuit is
provided corresponding to an intersection of a data line and a scanning line, and
further includes a first selector, a second selector, and a driving transistor,
the driving transistor is configured to supply a current corresponding to a voltage of a gate node to the light-emitting element,
in the first period,
the first selector electrically connects one end of the first capacitance element to the data line when the scanning line is selected,
the second selector electrically connects one end of the second capacitance element to the gate node,
in the second period,
the first selector electrically connects the one end of the second capacitance element to the data line when the scanning line is selected, and
the second selector electrically connects the one end of the first capacitance element to the gate node.
4. The projection device according to claim 3 , wherein
the first selector includes
a first switching element that is in an on state or an off state between the data line and the one end of the first capacitance element, and
a second switching element that is in the on state or the off state between the data line and the one end of the second capacitance element, and
the second selector includes
a third switching element that is in the on state or the off state between the one end of the first capacitance element and the gate node, and
a fourth switching element that is in the on state or the off state between the one end of the second capacitance element and the gate node.
5. The projection device according to claim 4 , wherein
the pixel circuit includes
a fifth switching element connected in series to the driving transistor between a high level power supply wiring line and a low level power supply wiring line.
6. The projection device according to claim 5 , wherein
in all or a part of the first period or the second period,
the fifth switching element is in the on state.
7. The projection device according to claim 3 , wherein
the pixel circuit includes
a sixth switching element that brings the driving transistor into a diode-connected state.
8. The projection device according to claim 7 , wherein
the pixel circuit includes
a third capacitance element in which a threshold voltage of the driving transistor is held, and
the third capacitance element
is interposed between the one end of second capacitance element and the gate node
in the first period and
is interposed between the one end of the second capacitance element and the gate node in the second period.
9. A method for controlling a projection device including
a display panel including a pixel circuit including a first capacitance element and a second capacitance element, and a light-emitting element that emits light, having luminance corresponding to a current, in a predetermined direction, and
an optical path shifting element configured to shift an optical path of light emitted from the light-emitting element to a first optical path and a second optical path, wherein
in a first period,
a voltage corresponding to a current supplied to the light-emitting element is held in the first capacitance element,
in a light-out period after the first period,
the light-emitting element is off, and
the optical path is shifted from the first optical path to the second optical path,
in a second period after the light-out period,
a current corresponding to the voltage held in the first capacitance element is supplied to the light-emitting element,
a voltage corresponding to the current supplied to the light-emitting element is held in the second capacitance element, and
the second optical path is maintained.