COAXIAL LINE, TRANSMISSION AND TRANSMISSION RECEPTION MODULE FOR MILLIMETER WAVE RADAR, AND ELECTRONIC CIRCUIT MODULE FOR HIGH FREQUENCY

摘要

PROBLEM TO BE SOLVED: To improve transmission precision of an electronic circuit module for high frequency by suppressing dielectric loss and transmission loss of a coaxial line in an electronic circuit handling a high frequency electric signal. SOLUTION: This coaxial line is constituted by sealing a lead 11 in a through-hole 14 by a glass dielectric 12. Its dielectric loss is set 0.01 or less and its dielectric constant is set 3 or more. Flatness of an end face in the axial direction of the dielectric is set within±(L×10%) to achieve these characteristics, when it is expressed by a degree of projection and recess by multiplying a distance L between the lead 11 and a peripheral fringe of the through-hole 14 by percentage. The eccentricity of the lead 11 and the inclination against end face H in the axial direction of the dielectric 12 are a half or less of a diameter of the lead 11. The dielectric is made of borosilicate glass, and air bubbles contained in the dielectric are 30 vol.% or less of the dielectric. The dietectric contains 65 to 75 wt.% of silicic acid, 1 wt.% or less of lithium oxide, and 1 to 3 wt.% of sodium oxide and potassium oxide.