Infrared thermography is a whole field, noncontact, and nondestructive characterization technique widely used for the investigation of subsurface features in various solid materials (conductors, semiconductors, and composites). Increased demand for greater subsurface probing in thermal nondestructive testing is often thwarted by the probing high peak power into the sample, for which narrow pulse operation is usually used. The technique of pulse compression offers a means of increasing the average power available to illuminate test specimen without any loss of the depth resolution needed for the tactical requirements. This is accomplished by transmitting a wide pulse in which the incident heat flux is frequency modulated and then, by proper signal processing methods, causing a time compression of the received signal to a much narrower pulse of high effective peak power. For the demonstration, a mild steel sample having flat bottom holes at various depths is introduced and detection capability of the proposed approach has been studied.

1.
X. P. V.
Maldague
,
Theory and Practice of Infrared Technology for Nondestructive Testing
(
Wiley
,
New York
,
2001
).
2.
D. P.
Almond
,
P.
Delpech
,
M. H.
Beheshtey
, and
W.
Peng
,
Proc. SPIE
2944
,
256
(
1996
).
3.
N. P.
Avdelidis
and
D. P.
Almond
,
Infrared Phys. Technol.
45
,
103
(
2004
).
4.
J. W.
Maclachlan-Spicer
,
W. D.
Kerns
,
L. C.
Aamodt
, and
J. C.
Murphy
,
Proc. SPIE
1467
,
311
(
1991
).
5.
N. P.
Avdelidis
and
D. P.
Almond
,
NDT & E Int.
37
,
353
(
2004
b).
6.
D. L.
Balageas
,
J. C.
Krapez
, and
P.
Cielo
,
J. Appl. Phys.
59
,
348
(
1986
).
7.
D. P.
Almond
and
S. K.
Lau
,
Appl. Phys. Lett.
62
,
3369
(
1993
).
8.
S. M.
Shepard
,
J. R.
Lhota
, and
A.
Rubadeux
,
Opt. Eng.
42
,
1337
(
2003
).
9.
R. E.
Martin
,
A. L.
Gyekenyesi
, and
S. M.
Shepard
,
Mater. Eval.
61
,
611
(
2003
).
10.
M. B.
Saintey
and
D. P.
Almond
,
NDT & E Int.
30
,
291
(
1997
).
11.
D. T.
Wu
and
G.
Busse
,
Rev. Gen. Therm.
37
,
693
(
1998
).
12.
G.
Busse
,
Appl. Phys. Lett.
35
,
759
(
1979
).
13.
G.
Busse
and
P.
Eyerer
,
Appl. Phys. Lett.
43
,
355
(
1983
).
14.
G.
Busse
,
D.
Wu
, and
W.
Karpen
,
J. Appl. Phys.
71
,
3962
(
1992
).
15.
S.
Quek
,
D. P.
Almond
,
L.
Nelson
, and
T.
Barden
,
Meas. Sci. Technol.
16
,
1223
(
2005
).
16.
X. P. V.
Maldague
,
Mater. Eval.
6
,
1060
(
2002
).
17.
X. P. V.
Maldague
and
J.
Marinetti
,
J. Appl. Phys.
79
,
2694
(
1996
).
18.
X. P. V.
Maldague
,
F.
Galmiche
, and
A.
Ziadi
,
Infrared Phys. Technol.
43
,
175
(
2002
).
19.
V.
Dattoma
,
R.
Marcuccio
,
C.
Pappalettere
, and
G. M.
Smith
,
NDT & E Int.
34
,
515
(
2001
).
20.
C.
Meola
,
G. M.
Carlomagno
, and
G.
Giorleo
,
J. Mater. Process. Technol.
155
,
1132
(
2004
).
21.
R.
Mulaveesala
and
S.
Tuli
,
Appl. Phys. Lett.
89
,
191913
(
2006
).
22.
R.
Mulaveesala
and
S.
Tuli
,
Mater. Eval.
63
,
1046
(
2005
).
23.
R.
Mulaveesala
,
P.
Pal
, and
S.
Tuli
,
Sens. Actuators, A
128
,
209
(
2006
).
24.
S.
Tuli
, and
R.
Mulaveesala
,
Quantitative InfraRed Thermography Journal
2
,
41
(
2005
).
25.
N. P.
Avdelidis
,
C.
Ibarra-Castanedo
,
X.
Maldague
,
Z. P.
Marioli-Riga
, and
D. P.
Almond
,
Infrared Phys. Technol.
45
,
291
(
2004
).
26.
D. R.
Wehner
,
High Resolution Radar
(
Artech House
,
Boston
,
1994
).
27.
M.
O’Donnell
,
IEEE Trans. Ultrason. Ferroelectr. Freq. Control
39
,
341
(
1992
).
You do not currently have access to this content.