.PS

thicklines_
Barrel: box invis ht 0.4 wid 1.5
Face: line invis up 1.7 from Barrel.e+(2.4,-1.7/2)

   arc rad 2.6 from Face.start to Face.end

eps = 0.03
   arc rad 2.6 from Face.start-(eps,0) to Face.end-(eps,0)
line from Barrel.nw to Barrel.ne then to Face.end
line from Barrel.sw to Barrel.se then to Face.start
arc cw from Barrel.sw to Barrel.nw rad Barrel.ht*1.2
ifdef(`pstricks_',`\psset{linecolor=white}
   e = 2.6*(1-sqrt(1-(1.7/(2*2.6))^2))
   line from Face.start+(e+0.05,0) to Face.end+(e+0.05,0)
   \psset{linecolor=black}')

Cathode: Barrel.w+(0.3,0)
Term: Barrel.w+(-0.25,0)
dcath = 0.13
dan = 0.12

line from Cathode up   dcath/2 left dcath/2 then to Term.x,Cathode.y+dcath/2
   dot
line from Cathode down dcath/2 left dcath/2 then to Term.x,Cathode.y-dcath/2
   dot

hole = 0.06
Hole: line invis up hole from Cathode+(0.5,-hole/2)
line from Hole.end     up dan-hole/2 then to Term.x,Cathode.y+dan; dot
line from Hole.start down dan-hole/2 then to Term.x,Cathode.y-dan; dot

platewid = 0.25
platesep = 0.15
Plates: box invis wid platewid ht platesep at Barrel.e+(-platewid/2,0)
line right platewid from Plates.nw
line right platewid from Plates.sw
line up 0.3 from Plates.n
line down 0.3 from Plates.s

thicklines_(1.4pt)
ifdef(`pstricks_',`\psset{linecolor=gray}')

line from Cathode+(0.03,0) to Plates.c
Spot: 0.9<Face.start,Face.end>
line from 0.02<Plates.e,Spot> to 1.007<Plates.e,Spot>
#spline from 0.04<Plates.e,Spot> to last line.start \
#   then to Plates.c+(0.02,0) then to Plates.c
arc cw from last line.start to 2nd last line.end rad 1.5

ifdef(`pstricks_',`\psset{linecolor=black}')
thinlines_

arrow <- from Cathode+(0.2,0.06) up 0.5 left 0.3
   "{\sl electron}" above "{\sl gun}" above

arrow <- from Plates.nw+(0,0.06) up 0.5 left 0.3
   "{\sl deflection}" above "{\sl plates}" above

arrow <- from 0.5<Plates.e,Spot>+(0,0.06) up 0.5 left 0.3
   "{\sl electron beam}" at Here+(-0.3,0) above

spline <- from 1.015<Plates.e,Spot> right 0.1 up 0.1 then up 0.1 \
   then up 0.1 left 0.1
   "{\sl spot of light}sp_" rjust

"{\sl vacuum}sp_" at Face.c+(-0.4,0) rjust

arrow <- from Face.start+(0.1,0.5) left 0.6*1.4 down 0.3*1.4
   "{\sl phosphor coating}sp_" rjust

arrow <- from 0.2<Barrel.se,Face.start> left 0.6 down 0.3
   "{\sl glass enclosure (tube)}sp_" rjust
.PE