Constantine Macricostas
Analyst
Thank you, Pete. And good morning, everyone. Please turn to Slide 3 in our slide presentation. In Q3, quarterly sales of $116.6 million, ahead of our revised guidance. IC sales were $90.3 million. High-end sales were $27.4 million, down $3.9 million sequentially. It was offset by an increase in mainstream sales, which were $5.1 million or 9% sequentially.
We are pleased that the mainstream business picked up this quarter. We showed increased demand because many of our mainstream customers. It was expected, also was unexpected because of decline in demand from high-end customers in the second half of July. This decline, however, was limited to a few customers, mainly memory companies that scale back orders.
Turning to the display side, sales for FPD photomask were $26.3 million during the quarter, down $2 million sequentially. High-end sales were $17.3 million, down $1.9 million sequentially. On the display side, we experienced softness at the leading edge. Demand for high-end FPD declined late in the quarter. We believe this was related to economic uncertainty and slower demand for our advanced devices in mature markets.
Due to strong cost control throughout the quarter, we improved our gross and operating margin sequentially by 230 and 190 basis points, respectively. As a result, we generated earnings per share of $0.16, which were within our initial guidance. EBITDA was $38 million, up $2 million sequentially.
In summary, despite future economic trends, we believe that we're in excellent position. We have strong global operations, leading-edge technology, a strong balance sheet and we believe we're the most cost-efficient photomask supplier in the market. In the near term, we are focused on strengthening our competitive position in a conscious market. We are seeing momentum in our mainstream customers' orders and our high-end customers have a strong node migration plans. [indiscernible] these advanced nodes that goes both memory and logic. Longer-term, we believe this trend will yield to continue growth and market share gain for Photronics and we remain disciplined in our approach to controlling cost.
Before I turn the call over to Sean, I would like to thank the entire Photronics global organization for the effort during the quarter. And now I will turn the call over to Sean. Sean?