Method of detecting and compensating fail pixel in hologram optical storage system

A method of detecting fail pixels in a holographic storage system, comprising steps of:

• sequentially providing a plurality of image frames to show on a data plane to make all pixels on the data plane capable of outputting a light state and a dark state;
• sequentially recording the image frames presented on the data plane in a storage medium;
• sequentially receiving the image frames recorded in the storage medium by using a detecting apparatus to make each pixel on the detecting apparatus can receive both the light state and the dark state and be capable of outputting a sensing signal with different values corresponding to the light state and the dark state received by the pixel;
• defining a sensing-difference value, which is a difference of the different values of the sensing signal outputted by one pixel;
• comparing the sensing-difference value with a threshold value;
• defining the corresponding pixel is a good pixel if the sensing-difference value is larger than the threshold value;
• defining the corresponding pixel is a fail pixel if the sensing-difference value is smaller than the threshold value;
• providing a whole-light laser beam and a whole-dark laser beam to emit to the detecting apparatus;
• defining the fail pixel is on the data plane if the corresponding pixel can sequentially output a corresponding large-amplitude sensing signal and a corresponding small-amplitude sensing signal;
• and
• defining the fail pixel is on the detecting apparatus if the pixel cannot sequentially output the corresponding large-amplitude sensing signal and the corresponding small-amplitude sensing signal.

A method of compensating fail pixels in a holographic storage system, applied to a region within a data plane and the region contains a first number of light states and a second number of dark states, comprising steps of:

• defining a light-state sum via counting the light states generated by pixels on a detecting apparatus corresponding to the region within the data plane;
• defining a dark-state sum via counting the dark states generated by pixels on the detecting apparatus corresponding to the region within the data plane;
• defining a fail pixel outputting the dark state if the light-state sum is equal to the first number and the dark-state sum is not equal to the second number;
• and
• defining the fail pixel outputting the light state if the light-state sum is not equal to the first number and the dark-state sum is equal to the second number.

A method of detecting and compensating fail pixels in a holographic storage system, applied to a region within a data plane and the region contains a first number of light states, comprising steps of:

• sequentially providing a plurality of image frames to show on a data plane to make all pixels on the data plane capable of outputting a light state and a dark state;
• sequentially recording the image frames presented on the data plane in a storage medium;
• sequentially receiving the image frames recorded in the storage medium by using a detecting apparatus to make each pixel on the detecting apparatus can receive both the light state and the dark state and be capable of outputting a sensing signal with different values corresponding to the light state and the dark state received by the pixel;
• defining a sensing-difference value, which is a difference of the different value of the sensing signal outputted by one pixel;
• defining the corresponding pixel is a fail pixel if the sensing-difference value is smaller than a threshold value;
• defining a first number of light states in a region within the data plane;
• defining a light-state sum via counting the light states generated by pixels on the detecting apparatus corresponding to the region within the data plane if the fail pixel is on the region;
• defining the fail pixel outputting the light state if the first number is not equal to the light-state sum;
• and
• defining the fail pixel outputting the dark state if the first number is equal to the light-state sum.