diff --git a/Absorption-Imaging-Class.md b/Absorption-Imaging-Class.md
index afea518..fdfce37 100644
--- a/Absorption-Imaging-Class.md
+++ b/Absorption-Imaging-Class.md
@@ -1,5 +1,23 @@
 This is a class for getting data of absorption imaging form three standard images (with atoms, without atoms, dark).
 
+# Properties
+* **self.path** *(unkown)*: path of the hdf5 file, produced by lyse moduel in LabScript.
+* **self.data_handle** *(class)*: handle of lyse.Run(self.path) in LabScript.
+* **self.camera_orientation** *(string)*: see the defination of absorption_imaging.\_\_init\_\_
+* **self.camera_label** *(string)*: see the defination of absorption_imaging.\_\_init\_\_
+* **self.image_atoms** *(2D numpy array)*: storing the data of the fist image.
+* **self.image_background** *(2D numpy array)*: similar to previous one
+* **self.image_dark** *(2D numpy array)*: similar to previous one
+* **self.image_absorption** *(2D numpy array)*: similar to previous one
+* **self.detuning** *(float)*: laser beam detuning in Hz!!!
+* **self.intensity** *(float)*: laser beam intersity at atom cloud in (W/m^2)
+* **self.beam_energy** *(float)*
+* **self.atom_number**
+* **self.transition**
+* **self.camera**
+
+# Functions
+
 | absorption_imaging  | Absorption Imaging Class |
 | ------------- | ------------- |
 | absorption_imaging.\_\_init\_\_  | Initialization of the class  |
@@ -7,6 +25,7 @@ This is a class for getting data of absorption imaging form three standard image
 | absorption_imaging.get_image_absorption | Calculte the absorption imaging |
 | absorption_imaging.get_atom_number | Calculte the atom number accoring to the absorption imaging |
 | absorption_imaging.plot_result | Ploting the result |
+| absorption_imaging.get_beam_power| Calculate the laser pulse power shooting on camera |
 
 ## absorption_imaging.\_\_init\_\_
 > dylab.absorption_imaging(data_path, camera_orientation, camera_label, transition=None, camera=None, detuning=None, intensity=None)
@@ -44,3 +63,9 @@ It can set the searching name of those three satandard images. The defualt names
 >  dylab.absorption_imaging.get_image_absorption():
 
 It will calculate the absorption imaging, integrating in \_\_enter\_\_ function
+
+### Parameters:
+* Nothing
+
+### Return:
+* **self.image_absorption** *(2D numpy array, optional)*: A two deminsional numpy array, which stores the calculation result. It will also update the value storing in **self.image_absorption**, so it not necessary to pick up the returned handle.