阅读说明：本技术 一种降低像增强器点亮光源图像周围亮环亮度的方法 (Method for reducing brightness of bright ring around image of light source lighted by image intensifier ) 是由 李晓峰 苏德坦 陈超 常乐 吴永祥 于 2020-05-27 设计创作，主要内容包括：本发明属于真空光电器件领域,公开了一种降低像增强器点亮光源图像周围亮环亮度的方法,该方法在MCP输入端镀制金属膜层,镀制时的浸入深度为输入端通道直径的一半,镀膜层的厚度为20nm-150nm,镀制材料采用低二次电子发射系数的Pt/Pd/Ni/Ag/Au和/或Ir金属材料。本发明通过在输入端通道壁的上面再镀制一层二次电子发射系数较低的金属材料膜并覆盖原有的镍-铬电极镀膜的办法,降低了MCP输入端产生二次电子的数量,大大降低亮环对亮斑周边目标的干扰。本发明能够大大降低像增强器点光源图像周围亮环的亮度,使微光夜视仪能够在存在点光源的视场中观察目标,而少受到点光源亮点周围亮环的干扰。(The invention belongs to the field of vacuum photoelectric devices, and discloses a method for reducing brightness of bright rings around an image of a lighting source image of an image intensifier. The invention reduces the quantity of secondary electrons generated at the input end of the MCP and greatly reduces the interference of the bright ring on the target around the bright spot by plating a layer of metal material film with lower secondary electron emission coefficient on the wall of the input end channel and covering the original nickel-chromium electrode coating film. The invention can greatly reduce the brightness of the bright ring around the point light source image of the image intensifier, so that the low-light level night vision device can observe a target in the field of view existing in the point light source and is less interfered by the bright ring around the bright point of the point light source.)

1. A method for reducing brightness of a bright ring surrounding an image of a light source illuminated by an image intensifier, comprising:

and plating a metal film layer with a low secondary electron emission coefficient at the input end of the MCP, wherein the immersion depth during plating is half of the diameter of a channel at the input end.

2. The method of claim 1, wherein the step of reducing the brightness of a bright ring surrounding an image of an image intensifier illumination source comprises: the metal material of the metal film layer plated with the low secondary electron emission coefficient is Pt/Pd/Ni/Ag/Au and/or Ir.

3. The method of claim 1, wherein the step of reducing the brightness of a bright ring surrounding an image of an image intensifier illumination source comprises: the thickness of the prepared metal plating film layer is 20nm-150 nm.

4. The method according to any one of claims 1 to 3, wherein the plating step comprises:

s1 preparation

Setting the temperature of the vacuum oven at 150 ℃ for standby;

s2 cleaning

2.1 firstly placing MCP into an MCP cleaning frame, then placing the MCP cleaning frame into a beaker, placing ethyl propanol into the beaker, and ensuring that the liquid level of the ethyl propanol in the beaker submerges the MCP cleaning frame by at least 30mm,

2.2 putting the beaker into an ultrasonic cleaning machine, cleaning for 5-8 minutes,

2.3 taking out the MCP cleaning rack, putting the MCP cleaning rack into a vacuum oven, and vacuumizing the oven, wherein the vacuum degree of the oven is better than 5 × 10^-1Pa, baking the MCP cleaning rack and the MCP in a vacuum oven for at least 1 hour,

2.4 after baking is finished, stopping vacuumizing, filling nitrogen into the vacuum oven, opening the vacuum oven when the air pressure inside and outside the oven is balanced, taking out the MCP, and putting the MCP into a packaging box;

s3 coating film

3.1 taking the MCP out of the packaging box and putting the MCP into an MCP coating fixture, then putting the MCP coating fixture into a coating machine,

3.2 controlling the immersion depth of the original metal electrode at the input end of the MCP to be half of the diameter of a channel,

3.3 close the door of the coater and start to vacuumize, when the vacuum degree of the coater is better than 5 × 10^-3When Pa, the evaporator is opened to start coating,

3.4 controlling the evaporation rate to be not more than 2nm/s, controlling the revolution rate of the film plating machine to be 10-15 r/min, stopping vacuumizing after film plating is finished, and filling nitrogen into a cavity of the film plating machine.

S4 finishing the film coating

When the internal and external pressure of the vacuum chamber of the coating machine reaches balance, the door of the coating machine is opened, the MCP coating fixture is taken out, then the MCP is taken out from the fixture and immediately placed in a packaging box of the MCP.

5. The method of claim 4, wherein the step of reducing the brightness of a bright ring surrounding an image of the image intensifier illumination source comprises:

the immersion depth of the original metal electrode at the input end of the MCP is controlled to be half of the diameter of the channel by 3.2, and the immersion depth is controlled by controlling the included angle theta between the evaporation source and the axis of the MCP, particularly by adjusting the distance between the evaporation source and the MCP; the larger the included angle is, the shallower the depth is, and the smaller the included angle is, the deeper the depth is.

6. The method of claim 5, wherein the step of reducing the brightness of a bright ring surrounding an image of an image intensifier illumination source comprises:

and the immersion depth of the original metal electrode is controlled to be half of the diameter of the channel by controlling the included angle theta between the evaporation source and the axis of the MCP, and the specific included angle theta is 63 degrees.