三合一假SIM卡托在生产过程中的测试应用

   以下是原始参考资料

         Track Location Cards-Accuracy/Precision Note

        When we produce a Track Location Card which places the tracks, for example, at 0.8mm above the ISO centerline. we check the actual placement of the tracks in thefollowing way:

1. Apply magnetic viewing fluid on the magnetic stripe permitting a visual examinationof the encoded flux transitions.

2.A measuring microscope equipped with X & Y digital calipers with a instrumenterror of+ 0.003 mm.

3.The hairline of the microscope is targeted at the top reference edge of the card and theX caliper zeroed. The microscope stage is moved by means of the X caliper until thehairline is positioned at the top of the flux transitions on Track 2. We only measurethe top of Track 2 since the track width and other track positions are fixed (three trackhead). See below for head dimensions and measured distances

Note: Several accuracy & precision factors:

     The magnetic viewing fluid make the magnified flux transitions appear somewhat fuzzyand thus it is the microscope operator's judgment of where the tops of the flux transitionsare positioned. Part of what makes the flux transitions fuzzy is fringing from theencoding head. The three track encoding head track widths are stated as 0.110 + 0.003inches (2.794 +0.08 mm). Fringing effects cause the appearance of the flux transitions tomeasure 3.1 + 0.05 mm. The extent that the magnetic viewing fluid can be attracted to thedecreasing magnetic field in the fringe portion is a factor on where the flux transitions areviewed.

Key dimensions:

     Track 1, 2 or 3 width (head): 2.794  0.08 mmTrack 1, 2 or 3 width (measured): 3.06 + 0.05 mm

Gap between Track 1 and Track 2 (measured): 0.26  0.01 mmGap between Track 2 and Track 3 (measured): 0.46 +0.01 mm

Encode head moves laterally on stepper motor under software controlHead offset precision: 0.025 mm per step

Measured track position and expected tolerances from a Track Card with a 0.8 mm abovethe ISO centerline is shown on the next page.

Example of a 0.8 mm high track offset card: 8.715 mm - 0.8 mm + 0.05 = 7.915 + 0.05mm

电 话：137-5119-6353

手 机：138-2999-7590

邮 箱：norman@wingiant.net/

地 址：广东省东莞市虎门居岐工业区平安路31号