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锆钛酸铅镧陶瓷(PLZT)应力偏压铁电光导器件已经报导过。他们所用结构为透射式,(在读出操作中,光通个整个器件)。透射式器件具有几个缺点:(a)对于读出光的波长,光导膜必须具有低的损耗。(b)在一个透射式的器件中,不能同时进行写入与读出,除非光导膜对读出光的波长没有反应。(c)假设希望低介入损耗,陶瓷片必须厚到足够产生一个完全半波长的延迟(一般需要片厚为150微米左右)。在应力偏压器件中,分辨率受到与片厚有关的边纹区域所限制(最小分辨元约为1/3片厚)。因此,陶瓷片尺寸必须足以适应所予期的信息元的数目,并且假设使用一个厚片,则器件的分辨率有明显的各向异性,(平行于张力的线条的分辨率小于垂直于张力的线条的分辨率)。在使用薄陶瓷片时,这个效应减少了。
Lead-lanthanum zirconate titanate (PLZT) stress-biased ferroelectric devices have been reported. The structure they use is transmissive, (in the read operation, the entire device passes through). Transmissive devices have several disadvantages: (a) The light guide film must have low loss for the wavelength of the readout light. (b) In a transmissive device, both writing and reading can not be performed at the same time unless the light guide film does not react to the wavelength of the readout light. (c) Assuming low insertion loss is desired, the ceramic chip must be thick enough to produce a complete half-wavelength delay (typically requiring a slice thickness of about 150 microns). In stress-biased devices, the resolution is limited by the area of the fringe associated with the slice thickness (the minimum resolution is about 1/3 the slice thickness). Therefore, the size of the ceramic sheet must be sufficient to accommodate the number of information elements presented and assuming a thick slab, the resolution of the device is significantly anisotropic (the resolution of the lines parallel to the tension is less than the resolution of the lines perpendicular to the tension Resolution). This effect is reduced when using thin ceramic sheets.