Hayato Takasago

New trimming technology of a thick film resistor by the pulse voltage method

To realize a noncut trimming method without any damage to the resistor surface of thick-film resistors for electronic devices, a pulse voltage trimming method (PVTM) has been developed for resistors of less than 0.5 mm/sup 2/. This trimming method combines coarse and fine adjustments which are, respectively, due to pulse peak voltage and the number of pulse groups. The PVTM ensures resistance accuracy with an error of less than 1%. High-frequency characteristics and current noise of the trimmed resistors are considerably improved by this trimming technique, and there is no loss in the power handling capability for the trimmed resistors. These advantageous features are obtained by the increased number of conductive paths in the trimmed resistors. >

Effective evaluation of anisotropic conductive film

An effective evaluation technique for ACF (anisotropic conductive film) was established by measuring viscoelasticity characteristics, peel strength, and connection resistance before and after the ACF pressure cooker test (15 hr). It was confirmed that this technique is a useful method for selecting optimum ACF bonding conditions. It was clarified that an ACF having metal particles as conductive particles was the optimum ACF for 100- mu m-pitch bonding. The intention is to fabricate a high-resolution TFT-LCD (liquid crystal display) by using this evaluation method.<<ETX>>

Optimum design of color pixel arrangement for 5-in diagonal TFT-LCD suitable for character and TV images

A new GRGB arrangement used for a 5-in TFT-LCD enables the total number of pixels to be decreased to 2/3 of the conventional RGB stripe arrangement. Adopting a signal compensation technique, 15*20 legible characters are displayed. TV display quality for the GRGB arrangement is expected to remain similar to that for the RGB stripe arrangement. A normalization method which is effective for comparisons of different LCTVs is proposed. It is concluded that, when the values of pixel pitch ratio vertical to horizontal are nearly 1/3, 1/2, and 1, the optimum color pixel arrangements are the RGB, GRGB, and RGB delta arrangements, respectively. >