IPC-T-50F_.pdf.pdf - 第61页

Resin Smear 51.1506 Base material resin that covers the exposed edge of con- ductive material in the wall of a drilled hole. (This resin transfer is usually caused by the drilling operation). Resin-Rich Area 41.1505 The …

Rectangular Leads 36.1764

A lead form or leg shape whose cross section is rectangu-

lar in shape.

Reduction Marks 22.1316

A set of stylized patterns in the border area of an artwork

between which the photographic-reduction dimension is

deﬁned.

Reed 44.1230

A thin comb made of pressed steel wires between which

warp ends are drawn after passing through the needle eyes.

Reference Dimension 26.1231

A dimension without a tolerance that is used only for infor-

mational purposes that does not govern inspection or other

manufacturing operations.

Reference Edge 22.1232

The edge of a cable or conductor from which measure-

ments are made.

Reference Hole 22.1233

see ‘‘Tooling Hole.’’

Reference Master 24.1234

Artwork that is free of defects.

Reflection, Signal 21.1499

The portion of the electrical energy that is sent back toward

its source because the signal encountered a change in

impedance in the transmission line on which it is traveling.

Reflow Soldering 75.1500

The joining of surfaces that have been tinned and/or have

solder between them, placing them together, heating them

until the solder ﬂows, and allowing the surface and the sol-

der to cool in the joined position.

Reflow Spike 75.1235

The portion of the reﬂow soldering process during which

the temperature of the solder is raised to a value that is

sufficient to cause the solder to melt.

Regardless of Feature Size 22.1236

A geometric tolerance or datum reference that applies at

any increment of size of a feature that is within its size tol-

erance.

Registered Production Master 24.1237

A production master that incorporates physical registration

features.

Registration 50.1240

The degree of conformity of the position of a pattern (or

portion thereof), a hole, or other feature to its intended

position on a product.

Registration Mark 22.1315

A stylized pattern (symbol) that is used as a reference point

for registration.

Regression Analysis 91.1241

The use of statistics to investigate and model the relation-

ships between parameters and results.

Reliability 90.1501

The probability that a component,device, or assembly will

function properly for a deﬁnite period of time under the

inﬂuence of speciﬁc environmental and operatinal condi-

tions.

Removable Contact 37.1242

A type of connector contact that is not permanently

retained within the connector body or insert.

Render True Color 24.1243

The color aberrations of an optical system that have been

sufficiently corrected so as to allow a magniﬁcation device

to resolve the required details.

Repair(ing) 77.1502

The act of restoring the functional capability of a defective

article in a manner that recludes compliance of the article

with applicable drawings or speciﬁcations.

Repeat Set-Up Time 92.1244

The set-up time for a unit that is identical to one previously

evaluated.

Repeatability (Accept/Reject) Decisions 91.1503

The percentage of features that show the same acceptance

or rejection status on a minimum of three consective tests

using identical operating modes and conditions in a

statistically-signiﬁcant random sampling of three units.

Residue 76.1245

Any visual or measurable form of process-related contami-

nation.

Resin 40.1246

A natural or synthetic resinous material. (See also ‘‘Rosin’’

and ‘‘Synthetic Resin.’’)

Resin Flux 75.1247

A resin and small amounts of organic activators in an

organic solvent.

Resin Recession 60.1504

The presence of voids between the plating of a plated-

through hole and the wall of the hole as seen in microsec-

tions of plated-through holes that have been exposed to

high temperatures. (See Figure R-1.)

IPC-T-50F June 1996

Resin Smear 51.1506

Base material resin that covers the exposed edge of con-

ductive material in the wall of a drilled hole. (This resin

transfer is usually caused by the drilling operation).

Resin-Rich Area 41.1505

The location in a printed board of a signiﬁcant thickness of

unreinforced surface-layer resin that is of the same compo-

sition as the resin within the base material.

Resin-Starved Area 41.1507

The location in a printed board that does not have a suffi-

cient amount resin to completely wet out the reinforcing

material. (Evidence of this condition is often in the form of

low-gloss dry spots or exposed ﬁbers.)

Resist 52.1508

A coating material that is used to mask or protect select

areas of a pattern during manufacturing or testing from the

action of an etchant, plating, solder, etc. (See also

‘‘Negative-Acting Resist’’ and ‘‘Positive- Acting Resist.’’)

Resistance 21.1805

The restriction to the ﬂow of electrons, determined by

Ohms law; the quotient of DC voltage, applied to the

extremes of a conductor or insulator, and the current ﬂow-

ing through it.

Resistance Soldering 75.1248

Soldering by a combination of pressure and heat generated

by passing a high current through two mechanically-joined

conductors.

Resistance Welding 75.1249

Welding by a combination of pressure and heat generated

by passing a high current through two mechanically-joined

conductors.

Resistor Drift 92.1250

The change in resistance of a resistor caused by aging,

usually expressed a percent change per 1,000 hours.

Resolving Power 24.1509

The ability of a photographic system to maintain the sepa-

rate identity of parallel lines and spaces in a developed

image when their relative displacement is small.

Response Variable 91.1251

The dependent variable being studied.

Reversal Development 24.1252

The reversing of the tone of an image on a photographic

emulsion from that which can be accomplished with con-

ventional developing.

Reverse Current Cleaning 76.1253

see ‘‘Anodic Cleaning’’

Reverse Image 52.1254

The pattern of resist on a printed board that is used to allow

for the exposure of conductive areas for subsequent plat-

ing.

Reversion 96.1510

A chemical reaction in which a polymerized material par-

tially or completely degenerates to a lower polymeric state

or to the original monomer. (This is usually accompanied

by signiﬁcant changes in physical and mechanical proper-

ties.)

Rework 77.1511

The act of reprocessing noncomplying articles, through the

use of original or alternate equivalent processing, in a man-

ner that assures compliance of the article with applicable

drawings or speciﬁcations.

Ribbon Cable 37.1255

A ﬂat cable with round conductors.

Ribbon Interconnect (n.) 37.1256

A ﬂat narrow ribbon of metal used to make interconnec-

tions to lands, lead frames, etc.

Right Reading 24.1257

A phototool pattern-orientation that is the same as the art-

work master when it is viewed from the primary side of a

product. (See Figures M-2 and R-2.)

Right Reading Down 24.1512

An orientation of a phototool in which the pattern is right

and the emulsion is on the surface that is away from the

viewing surface. (See Figures M-2 and R-2.)

Right Reading Up 24.1513

An orientation of a phototool in which the pattern is right

reading and the emulsion is on the surface that is toward

the viewing surface. (See Figures M-2 and R-2.)

IPC-I-001047

Figure R–1 Resin recession

RESIN 

RECESSION

RESIN 

RECESSION

June 1996 IPC-T-50F

IPC-I-002768

Figure R–2 Printed board viewing orientations

Notes:

1. A precise definition of image tone and orientation necessitates that the orientation of the pattern and the legend be separately

identified. For example: Layer 1—Pos RR DN (Legend Corr. Read) or Layer 2—Pos RR UP (Legend Rev. Read) (There is no such

thing as wrong reading.)

2. By definition, all layer patterns are viewed from the same direction. (This view defines RR for the pattern appearance of all layers; this

is not the same as viewing the final board copper head on.)

3. Legend is usually correct reading when viewing the copper; therefore, on occasion alphanumerics must be reversed reading when

the pattern is right reading by definition.

4. Production master emulsion must be presented against the board copper in the stack up. Therefore, production master emulsion

orientation is opposite to individual copper layer orientation, i.e., if copper is RR UP by definition, corresponding production master

must be RR DN.

5. When specifying artwork tone and orientation, remember the board layup and the purpose of the artwork, i.e., file copy, artwork

master, or production master, etc.

6. In manual designs the artwork is usually prepared at an enlarged scale with tapes and other drafting aids. The artwork master is

produced from the artwork by photographic reduction.

7. In semi-automated designs, there may be no artwork by definition. Typically, an enlarged color-coded printed wiring layout on a

gridded format is prepared for subsequent digitizing and photoplotting. This procedure may yield intermediate phototools which can

be photographically processed into an artwork master or it may directly yield an artwork master, working master, or production

master.

8. In fully automated systems, there is usually no artwork or printed wiring layout prepared. A computerized procedure from a form of

the electrical schematic by total computerization or a combination of computer and interactive design procedures. This procedure

may yield intermediate phototools or the artwork master, working master, or production master directly.

Multilayer

Printed

Boards

Corresponding

Registered

Production

Master

L3 - RR

L4 - RR UP (Legend Rev. Read)

L4 - RR DN

(Legend Rev. Read)

Emulsion

L1 - RR UP

(Legend Corr. Read)

L1 - RR UP

(Legend 

Corr. 

Read)

Viewing Primary Side

Copper

Substrate Base Material

Substrate

Base Material

COPPER

EMULSION

▼ ▼

▼

L2 - RR UP

▼

L3 - RR DN

▼

Copper

▼

Viewing Component Side

▼

L2 - RR

IPC-T-50F June 1996