Optical device and dirt level determining method

A dirt level determining method, applied to an optical device comprising a light source and an optical sensor, comprising:

• (a) emitting light to a surface by the light source;
• and
• (b) sensing optical data generated based on reflected light or scattering light of the light by the optical sensor;
• and
• (c) computing a dirt level of the surface according to the optical data;
• wherein the optical data comprises images, wherein each image of the images comprises at least one bright region and at least one dark region, wherein the step (c) computes the dirt level according to a proportion between an area of the bright region in the each image and an area of all regions of the each image or according to a number of the bright region in the each image;
• wherein a number of the images is larger than 2, wherein the step (c) computes the dirt level according to a proportion between an area of all of the bright regions in the images and an area of all regions of the images, or according to a number of all of the bright regions in the images.

An optical device, comprising:

• a processing circuit;
• a light source, configured to emit light to a surface;
• and
• an optical sensor, configured to sense optical data generated based on reflected light or scattering light of the light;
• wherein the processing circuit computes a dirt level of the surface according to the optical data;
• wherein the optical data comprises images, wherein each image of the images comprises at least one bright region and at least one dark region, wherein the processing circuit computes the dirt level according to a proportion between the dark region in the each image and all region of the image or according to a number of the dark region in the each image;
• wherein a number of the images is larger than 2, wherein the processing circuit computes the dirt level according to a proportion between all of the dark regions in the images and all region of the images, or according to a number of all the dark regions in the images.

A dirt level determining method, applied to an optical device comprising a light source and an optical sensor, comprising:

• (a) emitting light to a surface by the light source;
• and
• (b) sensing optical data generated based on reflected light or scattering light of the light by the optical sensor;
• and
• (c) computing a dirt level of the surface according to the optical data;
• wherein the optical data comprises images, wherein each image of the images comprises at least one bright region and at least one dark region, wherein the step (c) computes the dirt level according to a proportion between the dark region in the each image and all region of the image or according to a number of the dark region in the each image;
• wherein a number of the images is larger than 2, wherein the step (c) computes the dirt level according to a proportion between all of the dark regions in the images and all region of the images, or according to a number of all the dark regions in the images.