Photodetector, method of using the same, and image forming apparatus
AssigneeFuji Xerox Co., Ltd.
InventorTohru Hisano
Life of this patent
Estimating the term…
Abstract
A photodetector includes a light emitting portion for applying light, a light receiving portion for sensing the light, and a light guiding member 3 for guiding the light from the light emitting portion to a surface to be measured and guiding detection light from the surface to be measured to the light receiving portion. The light guiding member has a sheet-like optical transmission medium, which is disposed at a portion facing to the surface to be measured and transmits the light by internal reflection. The sheet-like optical transmission member has an optical aperture facing to the surface to be measured.
Claims20
A photodetector for detecting at least one of light reflected or scattered from a surface to be measured, comprising:
- a light emitting portion for emitting light;
- a light receiving portion for sensing light;
- and
- alight guiding member for guiding the light from the light emitting portion to the surface to be measured and guiding detection light from the surface to be measured to the light receiving portion,
- wherein the light guiding member has a sheet-like optical transmission medium disposed at a portion facing to the surface to be measured and transmits the light by internal reflection, and including an optical aperture facing to the surface to be measured.
A photodetector for detecting light reflected or scattered from a surface to be measured, comprising:
- a light emitting portion for emitting the light of two kinds of different wavelengths;
- a light receiving portion for sensing the light of the two kinds of different wavelengths;
- and
- a light guiding member,
- wherein the light guiding member includes an optical-transmission-path separating member for applying one of the light of the two kinds from the emitting portion to the surface to be measured and guiding detection light from the surface to be measured together with the other of light of the two kinds to the light receiving portion.
A light detecting method comrising:
- emitting light of two kinds of different wavelengths;
- guiding the light of the two kinds;
- applying one of the light of the two kinds to a surface to be measured;
- guiding detection light from the surface to be measured together with the other of the light of the two kinds;
- sensing the guided detection light and the guided other of the light of two kinds;
- performing division processing by the following formula:
- S(t)=VA(t)/VB(t)
- where VA(t) denotes the sensed detection light per time, and VB(t) denotes the sensed other of the light of the two kinds per time;
- and
- determining an optical detection result based on S(t)
A method for detecting a visible color material on an image carrying body of an image forming apparatus, the method comprising:
- emitting light;
- guiding and applying the emitted light to a surface of the image carrying body;
- sensing the light from the surface of the image carrying body;
- performing arithmetic processing by the following formula:
- S(t)={V max−V(t)}/{V max−V min}
- where V(t) denotes sensed light per time, Vmax denotes an average value of the sensed light V(t) of a portion at which the color material is absent, and Vmin denotes an average value of a state in which the color material is present and the sensed light V(t) is saturated;
- and
- determining an optical detection result based on S(t).
A method for detecting a visible color material on an image carrying body of an image forming apparatus, the method comprising:
- emitting light of two kinds of different wavelengths;
- guiding the light of the two kinds;
- applying one of the light of the two kinds to a surface to be measured;
- guiding detection light from the surface to be measured together with the other of the light of the two kinds;
- sensing the guided detection light and the guided other of the light of two kinds;
- performing arithmetic processing by the following formula:
- S(t)={VA max−VA(t)}/[{VA max−VA min}VB(t)/VBini]
- where VA(t) denotes the sensed detection light per time, VAmax denotes an average value of the sensed detection light VA(t) of a portion at which the color material is absent, VAmin denotes an average value of a state in which the color material is present and the sensed detection light VA(t) is saturated, VB(t) denotes the sensed other of the light of the two kinds per time, and VBmin denotes an initial setting value of VB(t);
- and
- determining an optical detection result based on S(t).
An image forming apparatus for forming visible image using a color material on a image carrying body, the image forming apparatus comprising:
- a detector for detecting the color material of the visible image on the image carrying body, the detector including:
- a light emitting portion for emitting light;
- a light receiving portion for sensing light;
- and
- a light guiding member for guiding the light from the light emitting portion to a surface of the image carrying body and guiding detection light from the surface of the image carrying body to the light receiving portion,
- wherein the light guiding member has a sheet-like optical transmission medium disposed at a portion facing to the surface of the image carrying body and transmits the light by internal reflection and including an optical aperture opposite to the surface of the image carrying body.
An image forming apparatus for forming visible image using a color material on a image carrying body, the image forming apparatus comprising:
- a detector for detecting the color material of the visible image on the image carrying body, the detector including:
- a light emitting portion for emitting the light of two kinds of different wavelengths, respectively;
- a light receiving portion for sensing the light of the two kinds of different wavelengths, respectively;
- and
- a light guiding member,
- wherein the light guiding member includes an optical-transmission-path separating member for applying one of the light of the two kinds from the emitting portion to a surface of the image carrying body and guiding detection light from the surface of the image carrying body together with the other of light of the two kinds to the light receiving portion.
Dependencies are inferred from the claim text.